innovation in commercial supersonic aircraft with
TRANSCRIPT
Kennesaw State UniversityDigitalCommons@Kennesaw State University
Senior Design Project For Engineers
5-2018
Innovation in Commercial Supersonic Aircraft withCandidate Engine for Next Generation SupersonicAircraftChristopher D. RoperKennesaw State University
Jordan FraserKennesaw State University
Alain J. SantosKennesaw State University
Follow this and additional works at: https://digitalcommons.kennesaw.edu/egr_srdsn
Part of the Aerospace Engineering Commons
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Recommended CitationRoper, Christopher D.; Fraser, Jordan; and Santos, Alain J., "Innovation in Commercial Supersonic Aircraft with Candidate Engine forNext Generation Supersonic Aircraft" (2018). Senior Design Project For Engineers. 1.https://digitalcommons.kennesaw.edu/egr_srdsn/1
InnovationinCommercialSupersonicAircraftwith
CandidateEngineforNextGenerationSupersonicAircraft
Authors:
ChristopherD.Roper|JordanFraser|AlainJ.Santos
KennesawStateUniversity
SouthernPolytechnicCollegeofEngineeringandEngineeringTechnology
DepartmentofSystemsandIndustrialEngineering
FacultyAdvisor:AdeelKhalid,Ph.D.
May2018
‐1‐
Abstract
The objective of this design study and competition - Next Generation Supersonic Candidate
Engine and Aircraft Design, is a response to a proposal and is motivated by NASA’s National
Research Announcement in 2006. The requirements of this design study are provided by AIAA
(American Institute of Aeronautics and Astronautics). The aircraft designed is a private business
class. The aircraft engine performs at a maximum speed of Mach 1.8 and supersonic cruise speed
of Mach 1.6 at 55,000 feet and a range of 4000 nmi. A generated mission profile through
considerations in flight regime will drive the design involved in the development of aircraft
characteristics. Interior cabin configurations are expected to support seating for up to 100
passengers. Using parametric cycle analysis, computational fluid dynamics, and system
modeling/experimentation, a refined aircraft and engine design will be produced. Detailed analyses
to meet the baseline requirements involve interpretation of trends of current generation aircraft
engines are considered for the finalized design. The performance of the aircraft engine will involve
calculations on wave drag, supersonic turbulent flow, and integrated methods of design of the
nacelle enveloped within the aircraft fuselage. Through these various iterative methods,
considerations in supersonic aircraft propulsion and aircraft design are presented. Projected
technical specifications are to be implemented for the next generation of supersonic aircraft
expected to be debuted in 2025. A robust composition of advanced material composites, methods
of manufacturing, and forecasted advancements in technology are utilized to develop a proposal
for the next generation of supersonic aircraft.
‐2‐
TableofContents
Chapter1:Introduction......................................................................................................................................................13
1.1‐SystemOverview&MajorDevelopments....................................................................................................13
1.2‐DesignRequirements&Specifications.........................................................................................................14
1.3‐TradeStudyItems..................................................................................................................................................15
1.4‐Concepts.....................................................................................................................................................................17
1.5‐VerificationPlan.....................................................................................................................................................20
1.7‐Simulation:ComputationalFluidDynamicAnalysis&FiniteElementAnalysis.........................21
1.8‐Test:WindTunnelTesting.................................................................................................................................21
1.9‐MinimumSuccessCriteria..................................................................................................................................21
Chapter2:LiteratureReview...........................................................................................................................................25
2.1‐AircraftDesigns.......................................................................................................................................................25
2.2‐EngineDesign..........................................................................................................................................................28
2.3‐NumericalMethods...............................................................................................................................................29
2.4‐ComputationalMethods......................................................................................................................................30
2.5‐EngineMaterial.......................................................................................................................................................30
2.6‐InletDesign...............................................................................................................................................................32
2.7‐EngineSelection......................................................................................................................................................33
2.8‐NozzleDesign...........................................................................................................................................................34
Chapter3:DesignApproach.............................................................................................................................................36
3.1‐ProblemSolvingApproach.................................................................................................................................36
‐3‐
3.2‐GanttChart................................................................................................................................................................37
3.3‐Flowchart...................................................................................................................................................................38
3.4‐Resources..................................................................................................................................................................39
Chapter4:EngineeringAnalysis.....................................................................................................................................41
4.1‐ParametricCycleAnalysis(PCA).....................................................................................................................41
4.2‐SupersonicWaveDragCalculations...............................................................................................................46
4.3‐InletDesignCalculations.....................................................................................................................................50
4.4‐InitialWeightCalculations.................................................................................................................................52
4.5‐ComputationalFluidDynamics........................................................................................................................54
4.6‐ComputationalMethods‐PARA.......................................................................................................................54
4.7‐ComputationalMethods‐TURBN...................................................................................................................57
Chapter5:ResultsandDiscussion.................................................................................................................................60
5.1‐HistoricalData.........................................................................................................................................................60
5.2‐TradeStudyEngineDesign................................................................................................................................60
5.3‐DiscussionofHistoricalData.............................................................................................................................61
Chapter6:Prototype............................................................................................................................................................62
6.1‐ComponentDesign..................................................................................................................................................62
6.2‐AircraftModel..........................................................................................................................................................65
6.3‐EngineModel...........................................................................................................................................................70
6.4‐InteriorDesignConfiguration...........................................................................................................................71
Chapter7:Conclusion..........................................................................................................................................................79
‐4‐
Chapter8:FutureWork......................................................................................................................................................81
Acknowledgements..............................................................................................................................................................83
References................................................................................................................................................................................84
Appendices...............................................................................................................................................................................87
AppendixA:ComputationalFluidDynamicAnalysis........................................................................................87
AppendixB:InletDesignAnalysisTradeStudies...............................................................................................88
AppendixC:NozzleDesignAnalysis........................................................................................................................91
AppendixD:CarpetPlots..............................................................................................................................................93
AppendixE:AircraftDesignComputerAidModels...........................................................................................97
AppendixF:EngineInitialConcepts.....................................................................................................................101
AppendixG:FinalEngineDesignPowerplant...................................................................................................103
AppendixH:HistoricalDataPlots..........................................................................................................................104
AppendixI:ParametricCycleAnalysis.................................................................................................................120
AppendixJ:TOPSISAnalysisandDesignMatrix..............................................................................................123
AppendixK:InitialWeightCalculations..............................................................................................................125
AppendixL:TURBNTurbineAnalysisProgram...............................................................................................126
AppendixM:Reflections.............................................................................................................................................129
AppendixO:Contributions........................................................................................................................................131
‐5‐
ListofTables
Table1:GeneralAircraftCharacteristics(Welge,etal,2010).........................................................13
Table2:BaselineEngine:BasicData,OverallGeometryandPerformance...............................15
Table3:Respectivecycletimesforsubsonicandsupersonicengines.........................................23
Table4:ThrustandTSFCrequirementsforaninstalledengine.....................................................23
Table5:ThrustandTSFCrequirementsforanuninstalledengine...............................................24
Table6:Thedesignmatrixusedtoidentifyapreliminaryselection............................................27
Table8:ParametricCycleAnalysisExcelSheet....................................................................................120
Table9:Tableofconstantvaluesforparametriccycleanalysis...................................................121
Table10:Detailedcalculationsinvolvingpropulsiveandthermalefficiency.........................121
‐6‐
ListofFigures
Figure1:GeneralEngineSchematic(AIAA).............................................................................................14
Figure2:Supersonicgeometryaircraftdesignsiteration1..............................................................17
Figure3:Supersonicinletdesigns,aerospikeanddoorpanelconfigurations..........................18
Figure4:Supersonicinletdesigns,bodydiffuseranddiamondshapedspikeconfigurations.
.......................................................................................................................................................................................18
Figure5:SupersonicVehicleDesignConcepts........................................................................................19
Figure6:SupersonicVehicleDesignConcepts........................................................................................19
Figure7:BoeingIcon‐II.....................................................................................................................................25
Figure8:Boeing765‐072Baircraftdesign...............................................................................................26
Figure9:Boeing765‐076Edesign................................................................................................................26
Figure10:LockheedN+2concept................................................................................................................27
Figure11:WideChordFanBlade.................................................................................................................28
Figure12:Screenshotfrom[26]showingGE’sconceptTAPSIIcombustor.............................29
Figure13:SupersonicPlugSpikeNozzle Figure14:SupersonicPlugNozzle.....................34
Figure15:Nozzlewithchevrons...................................................................................................................35
Figure16:ImplementedGanttChart...........................................................................................................38
Figure17:DesignFlowChart.........................................................................................................................39
Figure 18: Numerical and analytical wave drag estimation for high speed supersonic
compressibleflow.................................................................................................................................................49
‐7‐
Figure19:SupersonicspikeCFDanalysisforinletdesign................................................................50
Figure20:SupersonicpanelchannelCFDanalysisforinletdesign..............................................51
Figure21:SupersonicextendedandoptimizedpanelchannelCFDanalysisforinletdesign
(a)Pressure(b)MachNumber(c)Velocity...............................................................................................52
Figure22:Themissionprofileoftheaircraft..........................................................................................52
Figure 23: Computer Aid Model demonstrating cruise climb prior to supersonic cruise
mission.......................................................................................................................................................................54
Figure24:Inputparametersintotheprogram.......................................................................................55
Figure25:OutputvaluesfromtheprogrambasedoniteratedLPCPressureRatio..............56
Figure26:OutputvaluesfromtheprogrambasedoniteratedLPCPressureRatio..............57
Figure27:TURBNStage1calculations......................................................................................................58
Figure28:TurbineBladeProfile...................................................................................................................59
Figure29:TableofTurbineConstraints(AngularVel.vs.MeanRadius)...................................59
Figure30:EngineFanBlade Figure31:EngineFanHub...........................................................63
Figure32:NASACalculationsforNozzleBehavior...............................................................................63
Figure33:Modelsof:nozzle(a),plugdesign(b),fullyopenednozzleexit(c),fullyclosed
nozzleexit(d).........................................................................................................................................................64
Figure34:Isometricandprofileviewofsupersonicprototypeaircraft....................................65
Figure35:ComputerAidModelbodyloftingprocessofsupersonicaircraftvehicle............66
Figure36:Design1conceptwithdoubledeltastraightwinggeometry(isometricandright
siderespectivelyprofiles).................................................................................................................................66
‐8‐
Figure37:Design2conceptwithdoubledeltastraightwinggeometry(isometricandright
siderespectivelyprofiles).................................................................................................................................67
Figure38:Design3conceptwitharceddeltastraightwinggeometry(isometric,front,right
siderespectivelyprofiles).................................................................................................................................68
Figure39:Design3conceptwithcomputationalfluiddynamicmodelmeasuring(a)Mach
number,(b)pressure,and(c)temperaturerespectively....................................................................69
Figure40:DesignconceptwithenginelocationconfigurationforOrientation1(oneengine
above,withonebelow).......................................................................................................................................70
Figure41:DesignconceptwithenginelocationconfigurationforOrientation2(twoengines
belowfuselage)......................................................................................................................................................70
Figure42:Designconceptforsupersonicenginepowerplant(a)sideprofile(b)frontprofile
.......................................................................................................................................................................................71
Figure43:Standardconfigurationlayout.................................................................................................72
Figure44:Sideviewofstandardseating...................................................................................................72
Figure45:Overheadviewofstandardconfiguration(Left),............................................................73
Figure46:IsometricView(Right)................................................................................................................73
Figure47:Detailedviewofseating[28]....................................................................................................74
Figure48:Detailedviewofseating[28]....................................................................................................74
Figure49:Luxury/PremiumEconomySeating......................................................................................75
Figure50:Sideviewofseating......................................................................................................................75
Figure51:Overheadviewofconfiguration..............................................................................................76
Figure52:IsometricView(BottomRight)................................................................................................76
‐9‐
Figure53:Detailedviewsofmodernandupdatedluxuryclassseating.....................................77
Figure54:(a)ridesideprofileofsimulatedpressureandmachspeeds(b)Shearstressand
pressureformation(c)Acousticpowerlevelreadingatcruiseconditions.................................87
Figure55:TradeStudyandBaselineInletDesignChoiceSelection..............................................88
Figure56: Design1sidecutplotprofileviewfor:(a)Pressure(b)Velocity(c)Acoustic
PowerLevel.............................................................................................................................................................89
Figure57:Design2sidecutplotprofileviewfor:(a)Pressure(b)Velocity(c)Temperature
.......................................................................................................................................................................................90
Figure 58: Design 1 side cut plot profile view: (a) Pressure, (b) Mach Number, (c)
Temperature,and(d)Velocity........................................................................................................................91
Figure 59: Design 2 side cut plot profile view: (a) Pressure, (b) Mach Number, (c)
Temperature,and(d)Velocity........................................................................................................................92
Figure60:Design1conceptwithstraightdeltawinggeometry(isometric,front,rightside
respectivelyprofiles)...........................................................................................................................................97
Figure61:Design2conceptwithdoubledeltastraightwinggeometry(isometric,front,right
siderespectivelyprofiles).................................................................................................................................98
Figure62:Design3conceptwitharceddeltastraightwinggeometry(isometric,front,right
siderespectivelyprofiles).................................................................................................................................99
Figure63:Frontalnoseaircraftdesignbaseline: (isometric, right side, frontrespectively
profiles)...................................................................................................................................................................100
Figure64:Frontalnoseaircraftdesignextendednoseoptimization:(isometric,rightside,
frontrespectivelyprofiles).............................................................................................................................100
Figure65:EngineConcept.............................................................................................................................101
‐10‐
Figure66:ConceptNozzleGeometries....................................................................................................102
Figure67: Engine isometric and sideprofile of internal viewingof supersonic geometry
.....................................................................................................................................................................................103
Figure68:SpecificFuelConsumptionvsoverallefficiencyforcommercial/civilaircraft104
Figure69:BypassRatiovsOverallEfficiencyforcommercial/civilaircraft...........................104
Figure70:OverallPressureRatiovsOverallEfficiencyforcommercial/civilaircraft.......105
Figure71:Specificfuelconsumptionvsthrustforcommercial/civilaircraft........................105
Figure72:Graphofoverallefficiencyversusbypassratioformilitaryaircraft....................106
Figure73:SpecificfuelconsumptionvsOverallefficiencyformilitaryvehicles...................106
Figure74:Overallpressureratiovsoverallefficiencyformilitary/civilaircraft.................107
Figure75:Specificfuelconsumptionvsthrustformilitary/civilaircraft................................107
Figure76:OverallPressureRatiovsThrustforMilitaryAircraft................................................108
Figure77:BypassRatiovsThrustforMilitaryAircraft....................................................................108
Figure78:WeightvsThrustforMilitaryAircraft................................................................................109
Figure79:InletTemperaturevsThrustforMilitaryAircraft.........................................................109
Figure80:TSFCvsThrustforMilitaryAircraft....................................................................................110
Figure81:BypassRatiovsTSFCandFanPressureRatioforMilitaryAircraft......................110
Figure82:InletTemperaturevsOverallPressureRatioandTSFCforMilitaryAircraft...111
Figure83:InletTemperaturevsBypassRatioandTSFCforMilitaryAircraft.......................111
Figure84: Inlet Temperature vs Overall Pressure Ratio and EngineWeight forMilitary
Aircraft.....................................................................................................................................................................112
‐11‐
Figure85:InletTemperaturevsBypassRatioandEngineWeightforMilitaryAircraft...112
Figure86:OverallPressureRatiovsThrustforCommercialAircraft........................................113
Figure87:BypassRatiovsThrustforCommercialAircraft............................................................113
Figure88:WeightvsThrustforCommercialAircraft.......................................................................114
Figure89:TSFCvsThrustforCommercialAircraft............................................................................114
Figure90:FanPressureRatiovsBypassRatioforCommercialAircraft..................................115
Figure91:FanPressureRatiovsBPRvsSFCforSupersonicMilitaryAircrafts....................115
Figure92:FanPressureRatiovsOPRvsSFCforSupersonicMilitaryAircrafts....................116
Figure93:FanPressureRatiovsBPRvsEngineWeight forSupersonicMilitaryAircrafts
.....................................................................................................................................................................................116
Figure94:FanPressureRatiovsOPRvsEngineWeight forSupersonicMilitaryAircrafts
.....................................................................................................................................................................................117
Figure95:FanPressureRatiovsBPRvsEngineWeightforCommercialAircrafts.............117
Figure96:FanPressureRatiovsOPRvsSFCforCommercialAircrafts...................................118
Figure97:FanPressureRatiovsBPRvsEngineWeightforCommercialAircrafts.............118
Figure98:FanPressureRatiovsOPRvsEngineWeightforCommercialAircrafts.............119
Figure99:ParametricCycleAnalysisProgramforCandidateEngine(Trial1).....................122
Figure100:Designmatrixforpreliminaryselection.........................................................................123
Figure101:PrioritizationMatrixforTOPSIS........................................................................................123
Figure102:QualitativeScaleandFinalRankingforTOPSIS..........................................................123
Figure103:FinalizedTOPSISDataMatrix..............................................................................................123
‐12‐
Figure104:Normalized,criteria,weighteddata,idealsolution,distancefromthepositive,
andnegativematricesforTOPSIS................................................................................................................124
Figure105:SizingCalculation......................................................................................................................125
Figure106:InputsfortheBeguetRangeequation.............................................................................125
Figure107:BreguetRangeEquationcalculation................................................................................126
Figure108:TURBNStage2Analysis.........................................................................................................126
Figure109:TURBNStage3Analysis.........................................................................................................127
Figure110:TURBNStage4Analysis.........................................................................................................127
Figure111:TURBNStage5Analysis.........................................................................................................128
Figure112:TURBNStage6Analysis.........................................................................................................128
‐13‐
Chapter1:Introduction
1.1‐SystemOverview&MajorDevelopments
The progression of time ignites the invention of many exciting and daring
technologiesastheworldbecomesmoredemanding.Doctorsmusttravelacrossstatesto
retrieve organs, businessmen have to venture across countries to negotiate corporate
dealings, and everyone has to get somewhere faster. This dire need for promptness has
become the catalyst foraerospace leaders tobegindesigningnextgeneration supersonic
transportvehicles.Topowersuchforcefulandfastvehicles,newenginedesignsarebeing
exploredandcreated.NASAisoneofthemajorfacilitatorsofthisengineeringmovement.
What they need is an aircraft that goes beyond current supersonic business aircraft in
performancebutissmallerthanpastNASAairlinersofthesameclass.Theenginethatwill
beusedasareferencepointistheonedemonstratedinNASA/CR‐2010‐216842.Theaircraft
willhavetheusebaselinecharacteristicsshowninTable1.
Table1:GeneralAircraftCharacteristics(Welge,etal,2010)
‐14‐
Newmaterialswillbeexploredforthedifferentcomponentsintheenginebasedon
predicteddiscoveriesthatcouldbemadefromnowuntil2025.Thesematerialscanhelpwith
manyfactorsthatwillbestudiedingreatdetailandincorporatedintotheenginedesignand
performancetests.
By the completion of the project, the prototypewill show improvements in TSFC
(thrustspecificfuelconsumption)ofatleast5%withsignificantweightsavings,meetthe
cruise emissions goals, and address specified noise constraints (exit jet velocity). A
preliminaryschematicofourenginedesignisshowninFigure1withthemajorpartsbeing
labeled.
Figure1:GeneralEngineSchematic(AIAA)
1.2‐DesignRequirements&Specifications
The engine designed byTeam Supersonicwill power a transport vehicle that can
carry100passengersatMach1.6over4000nmi.Theenginewillbeadualspoolmixed‐flow
turbofan.Thebaselinefandiameteris87.5inches,andtheengineweightexcludingtheinlet
‐15‐
willbe13,000pounds.Thenewenginedesignwillbe,basedontradestudies,optimizedfor
minimum engine mass and fuel consumption by determining the best mixture of fan
pressureratio,overallpressureratio,bypassratio,andturbineentrytemperature.Itwillbe
alsooptimizedtomaximizetheflightrange.Usingthefactorsfromthetradestudies,possible
compromisescanbemadebetweenengineweightandfuelconsumptionontheaircraft's
performance.BelowinitialdesignspecificationscanbefoundinTable2.Theinitialinstalled
thrustcharacteristicsareshownbelowinTable4,andtheuninstalledonesareinTable5.
Table2:BaselineEngine:BasicData,OverallGeometryandPerformance
Fortheinlet,onemustbedesignedtooptimizeinternalperformanceandminimize
inletpropulsionsystemdrags.Thenozzlemustalsomeetcertaindesignspecificationsto
allowefficientsupersoniccruiseandmeetcurrentnoiserestrictions.Thiswillbedoneby
designing a convergent‐divergent noise‐attenuating nozzle. The nozzle will be made to
optimizethegrossthrustcoefficientandtominimizenozzlepropulsionsystemdrags.Many
differentmethodswillbeexploredfornoisereduction.
1.3‐TradeStudyItems
Athorough investigationwillbemadeonvaryingconditions to thegeometryandthe
parametric cycle analysis. The geometries selectedwill determine the supersonic engine
‐16‐
parameters.Usingadesignmatrix,acompilationofconceptdesignideaswillbeassessed,
andkeyfeaturesandhighlightswillbetakenintoconsiderationfortheappliedapproachin
the preliminary design. The parametric cycle analysis trade studies will investigate the
trendsassociatedwiththerespectivevariablestodetermineathoroughdescriptionofthe
overallperformanceofourenginedesign.Belowarealistoftradestudiesthatwillbedone.
● Geometry
○ InletGeometry
○ WingGeometry
○ Fuselage
○ EnginePlacement
● ParametricCycleAnalysis
○ FPRvs.BPRvs.MissionFuelBurn
○ OPRvs.T4.1maxvs.MissionFuelBurn
○ FPRvs.OPRvs.MissionFuelBurn
○ BPRvs.T4.1vs.MissionFuelBurn
○ FPRvs.BPRvs.cruiseTSFC
○ OPRvs.T4.1maxvs.cruiseTSFC
○ FPRvs.OPRvs.cruiseTSFC
○ BPRvs.T4.1vs.cruiseTSFC
○ FPRvs.BPRvs.engineweight
○ OPRvs.T4.1maxvs.engineweight
‐17‐
○ FPRvs.OPRvs.engineweight
○ BPRvs.T4.1vs.engineweight
This list of trade studies will guide the engine design. An analysis will be done
comparingvaluessuchasoverallpressureratio,turbineinlettemperature,overallpressure
ratiotomissionfuelburn,cruiseTSFCandEngineweight.Giventhattherequirementsfor
theenginedesignaretocreateanengine that increases theTSFCmarginby fivepercent
whilemaintainingalowerweight,analysisofthesetradestudyitemswillassistindesign
parametersfortheengine.
1.4‐Concepts
Conceptsketchesarecreatedtogenerateavisualontheaircraftandtheinletforthe
nacelle for the engine. Three view sketches for the aircraft as well as inlet designs are
covered.Thesesketchesareabasisfortheframeworkinwhichanalysiswillbedone.Below
aretheattachedconceptsketchesthatwillaidincreatingthefinalizedCADfortheaircraft.
Figure2:Supersonicgeometryaircraftdesignsiteration1
‐18‐
Figure3:Supersonicinletdesigns,aerospikeanddoorpanelconfigurations
Figure4:Supersonicinletdesigns,bodydiffuseranddiamondshapedspikeconfigurations.
‐19‐
Figure5:SupersonicVehicleDesignConcepts
Figure6:SupersonicVehicleDesignConcepts
‐20‐
1.5‐VerificationPlan
Analysis
Numerical analysis is conducted for the overall project. Using parametric cycle
analysis,empiricalequations,andinitialsizingcalculations,ananalysisoftheaircraftwas
made.Furtherapplicationsandstudiesforthisprojectarelaterdiscussedinthefollowing
chapters.
Simulation
By using simulations, a refined design can be accomplished. The main source of
simulationsforthisprojectarecompletedusingSolidWorks.ComputationalFluidDynamics
(CFD) allows for the simulationof air under various conditions.Themain condition this
project focuses on is supersonic cruise. CFD Simulations for the engine components and
aircraftdesignareseeninthefollowingchapters.
Testing
Testingforthisprojectwillbeset inplaceasaplanofactionforfuturework.The
mainscopeofthisprojectwastocreatemodelsandconductnumericalandcomputational
analyses.Furthertestingcanbegeneratedusingawindtunnelusing3Dprintedmodelsand
utilizingthewindtunnelatKennesawStateUniversity.Giventhescalingfactorswiththe
windtunnel,testingandexperimentationwillbeplacedunderfuturework.
1.6‐Analysis:ParametricCycleAnalysisandNumericalAnalysis
Designbaselineengineparametersaregiveninsection4ofAIAAsupersonicengine
design challenge. To conduct parametric cycle analysis, optimization techniques can be
performedwith various parameters such as: enginemass and fuel burn, based on trade
studiestodeterminethebestcombinationof:
1. Fanpressureratio
2. Bypassratio
‐21‐
3. Overallpressureratio
4. Turbineentrytemperature
Inordertohelpquantifyandtabulatethenumericalanalysisvalues,AIAAapproved
packagessuchas:AxSTREAMbySoftInWayInc,NumericalPropulsionSystemSimulation
(NPSS),GasTurb12.Thesesoftwarepackageswill serveasaguide inorder toshape the
computational fluid dynamic analysis and finite element analysis with respect to fan
pressureratio,bypassratio,overallpressureratio,andturbineentrytemperature.
1.7‐Simulation:ComputationalFluidDynamicAnalysis&FiniteElementAnalysis
The team will explore advanced and sophisticated computational simulations in
order to verify the design compliance matrix. CFD and FEA simulations will work
coincidentlywiththeparametriccycleanalysis.Thenumericalandanalyticalcalculations
will shape and structure the environmental conditions for both CFD and FEA. The next
proceedingstepswillallowaniterativedesignandsequentialprocess.
1.8‐Test:WindTunnelTesting
The teamwill undergo 3D physical printing processes for rapid prototyping. The
ideology allows for wind tunnel testing for aerodynamic design exploration. Possible
components to undergo dynamic testing are: fan blades, high pressure turbines, low
pressureturbines,aircraftwing,airfoils,thecompletedassemblyaircraftandengineetc.
1.9‐MinimumSuccessCriteria
Minimumsuccesscriteriaforthisprojectistodesigncomponentsforamixed‐flow
turbofan engine that meet the baseline requirements set forth by AIAA and create a
preliminary aircraft design to supplement the engine design. The minimum criteria for
‐22‐
deliverables on this project include the report, presentation, and video associated with
aeronauticsseniordesign.Someofthedesignspecificationsandgoalsareoutlinedbythe
objectives in the request reportbyAIAA.Basedon thedesigndecisions and calculations
throughoutthedurationofthisproject,effortswillbemadetofocusonmeetingbaseline
specificationsoutlined.Thedesignmustbeabletotake‐offfromstaticsea‐level.Thedesign
mustbeabletomeetcruiserequirementsandovercometheeffectsofwavedrag.
Thedesignmustbealsobeabletobeprototypedtogenerateascaled3Dmodelor
partstodisplay.UsingSolidWorks,aworkingCADmodelmustalsobeutilizedtosuccessfully
conductCFDandFEA analysis. Computation and studies of aworkingdesign are closely
dependentonhowmuchisaccomplishedindevelopingaworkingCADmodel.Throughwind
tunneltesting,amorethoroughunderstandingoftheaerodynamicdesigncanbeassessed
todetermineoutcomesandtooptimizeafinaldesignforreview.Belowarealistofspecified
conditions and requirements along with tabulated values for various conditions for the
engine.
Prototype:DevelopascaledmodelinSolidWorkstobeutilizedforfutureworkingregarding
windtunneltesting
CADModel: Generate a working CADmodel to utilize CFD and FEA analysis on engine
componentsandaircraft
BaselineEngineFanDiameter:87.5inches(7.29ft)
ConditionsforTake‐Off:StaticSea‐LevelConditions
ConditionsforCruise:55,000ft,Mach1.6
AsperAIAA,asetoftablesandvaluesareprovidedforastartingpointandwillaidin
startinganalysisontherequiredenginedesign.Eachtablewillprovidesetparametersare
variousconditionsduringflight.Withineachoftheseflightregimes,characteristicsofthe
enginearechanged.Forthisproject,thefocuswillbetooptimizethedesignbasedonthe
flightcharacteristicsduringcruise.Belowarethevarioustablesusedinthedesign.
‐23‐
Table3:Respectivecycletimesforsubsonicandsupersonicengines
LandingTakeoff(LTO)CycleDefinitions
Mode SubsonicEngines SupersonicEngines
Power(%) TimeinMode(min) Power(%) TimeinMode(min)
Takeoff 100 0.7 100 1.2
Climbout 85 2.2 65 2.0
Descent N/A N/A 15 1.2
Approach 30 4.0 34 2.3
Taxi/Idle 7 26.0 5.8 26.0
Table4:ThrustandTSFCrequirementsforaninstalledengine
InstalledEngineThrustandTSFCRequirements
Conditions Altitude(ft) Mach dTamb(F) FN(lbf)TSFC(lbm/hr/lbf)
SLS 0 0 0 64625 0.520
HotDayTake‐Off 0 0.25 27 56570 0.652
TransonicPinch 40550 1.129 0 14278 0.950
SupersonicCruise 52500 1.6 0 14685 1.091
‐24‐
Table5:ThrustandTSFCrequirementsforanuninstalledengine
UninstalledEngineThrustandTSFCRequirements
Conditions Altitude(ft) Mach dTamb(F) FN(lbf) TSFC(lbm/hr/lbf)
SLS 0 0 0 70551 0.494
HotDayTake‐Off 0 0.25 27 61190 0.620
TransonicPinch 40550 1.129 0 17197 0.804
SupersonicCruise 52500 1.6 0 16471 0.993
‐25‐
Chapter2:LiteratureReview
2.1‐AircraftDesigns
Various concept designs currently exist in the aerospace industry in regards to
supersonic flight.Anumberofaircraftwereselectedbasedon theappropriategeometry
necessaryforsupersonicconditions.Theeffectsofsupersonicwavedragplayasignificant
role inselectingthegeometriestoovercomeit.Mainfeaturesthatwereobservedarethe
finenessratio,winggeometry,engineplacement,nacelledesign,andseatingconfigurations.
DesignsfromBoeing,NASA,andLockheedwereselectedfortheprototypedesign.Beloware
theaircraftdesignswhichwereconsidered.
Figure7:BoeingIcon‐II
‐26‐
Figure8:Boeing765‐072Baircraftdesign
Figure9:Boeing765‐076Edesign
‐27‐
Figure10:LockheedN+2concept
Thesedesignsprovideinsightontheselectionofgeometriesatsupersonicspeeds.
Basedonasetofdesigncriteria,toolssuchasTOPSISanalysisanddesignmatriceswereused
to select the aircraft which proved themost effective inmeeting the requirements. The
design matrix allowed a preliminary observation on each aircraft design. The TOPSIS
analysisshowsamoreobjectifiedanddetailedselectionseenintheappendix.Thedesign
matrixshownbelow,willdisplaythethoughtprocessonapreliminaryselection.
Table6:Thedesignmatrixusedtoidentifyapreliminaryselection
‐28‐
2.2‐EngineDesign
The enginedesignhas to be suited for efficient and fast travel. For these reasons
certain engines may qualify as a baseline even though their original mission can be
extraordinarily different from the one of this project. Starting with the fan, major
considerationsarethebladeairfoil,materialselection,geometry,andconnectionmethods
(dovetail).“Thinbladesareidealfromanaerodynamicperspective,whereasthickerblades
are important structurally with respect to impact and vibratory stress tolerance” [23].
Becauseofthisandnewtechnologiesthathollowoutthefanbladestodecreasetorsional
rigiditybyupto16%[23],thickbladesproveidealforhighspeedengines.Fanbladescan
spinatspeedsgreaterthan2000rotationsperminuteattake‐offspeed.Thiscomeswith
bothstressesandcentrifugal forces thatcouldcausedamageover timeanddecrease the
aircraft’s timebetweenoverhaul.Havinghollowedoutbladesalsohelpsdecreaseoverall
engineweightandfuelconsumption.Increasingthrusttoachievesupersonicspeedscanstill
bedonejustbyincreasingthefandiameteroracceleratingtheflowintotheengine.
Figure11:WideChordFanBlade
Forthecombustionchamber,itseemednecessarytogowitharich‐burn,quick‐mix,
lean‐burn (RQL) combustor concept. “Itwas introduced in 1980 as a strategy to reduce
oxidesofnitrogenemissionfromgasturbineengines”[25]. It is thedominantcombustor
‐29‐
technologyinenginedesigntodaywithleaderssuchasPratt&Whitneycreatingtheirown
modelsknownasTALON(TechnologyforAdvancedLowNOx).“Duetosafetyconsiderations
andoverallperformance(e.g.stability)throughoutthedutycycle,theRQLispreferredover
leanpremixedoptionsinaeroengineapplications”[25].ThelatestRQLcombustorfoundwas
theTAPSIIcombustorbeingdevelopedbyGeneralElectricfortheContinuousLowerEnergy,
EmissionsandNoise(CLEEN)Program.Because“TAPSIIhassignificantreductionforall4
regulatedpollutantsandtheTAPSIItechnologyNOxemissionsareat39.3%ofCAEP/6(or
60.7%margintoCAEP/6),whichmeetstheCLEENNOxgoalof60%margintoCAEP/6,”the
TAPSIIcombustionsystemwaschosentobeintheteam’scandidateenginetohelpreduce
emissions[26].
Figure12:Screenshotfrom[26]showingGE’sconceptTAPSIIcombustor
2.3‐NumericalMethods
NumericalPropulsionSystemSimulation(NPSS)isamulti‐physicsandengineering
designnumericalsoftwareprogramthatenablesanenvironmentofvariousaircraftengines.
This powerful software allows the user to generate engine cycle models with various
components of engines, such as: inlet, compressor, combustion chamber, turbines, ducts,
‐30‐
nozzle,etc.Forseveralproblems,theengineerhastheabilitytodefinespecificdependent
andindependentvariables.NPSSallowsexecutionwithsolverconstraintstieddirectlytothe
problem solution. By doing so, this reduces the number of interacting software, thus
reducingerror[3].
2.4‐ComputationalMethods
Advancedcomputationalfluiddynamiccodesareimplementedinvariousindustry
andresearchinstitutionsinordertoexploretheeffectsofsonicboomenergydispersion.In
theN+2study,aresomeguidelinestoexploreandtesttwosupersonicconceptmodels:both
‐072Band‐076E[1].Fromthisextensivestudy,the‐076Emodelhasalowerboomsignature
butdoesnotmeetthestandardsdisplayedbyFAA.LessonsfromNASA’sdesignlowboom
tradestudieswillserveasabaselineinordertofurtherfuturesupersonicresearch.
2.5‐EngineMaterial
Historically,engineshavebeenmadeofmetal.Theyincorporatealuminum,steel,and
titanium for different purposes such as availability, strength, heat resistance, and cost.
Selectingthematerialofdifferentpartsdependsonthestresses,loads,andpurposeofthe
differentsections.Usually,“materialsarecharacterizedbytheirdamagetolerance,ductility,
highcyclefatigue(HCF)strength,andyieldstrength”[22].Becausethefrontoftheengine,
includingthefanandcompressorarethesomeofthemostimportantparts,theyhadtobe
built to resist impactdamage,be light, andbeable todecreaseaircraftdowntime.These
requirementsmadetitaniumaprimecandidate,andithasbeenusedwidelyinindustryfor
decades.
Astimeandtechnologyprogressed,newdesignrequirementsbecameimportantsuch
asengineweight,strength, fuelconsumption,andstrength.Currently, leaders in industry
suchasCFMInternational(GE/Snecma jointventure)andPrattandWhitneyhavebegun
‐31‐
research and the use of composite material. Examples would include the Boeing B787
DreamlinerandAirbusA350XWB,inwhichalmosthalfoftheaircrafts’structurebyweight
iscomposedofreinforcedplastics[23].“Similarly,thecontainmentcase,theretocontainthe
resultsofanybladeseparationandpreventhigh‐speeddebrisfromimpactingtheairframe
oraircraftsystems,cannowbecompositeratherthanmetalorametal‐compositehybrid
(typicallyaluminumover‐wrappedwitharamid).Weightsavedinthefan/containmentcase
pairinghasaknock‐oneffect,enablingcomponentssuchasshaftsandbearings,thepylons
whichattachtheenginetothewingandtheassociatedwingstructuretobemadelighter
also.Inaggregate,halfatonormorecanbesavedperengine,aprizewellworthhavinggiven
the high price of aviation fuel today” [23]. Metal‐composite hybrid materials such as
aluminumover‐wrappedwitharamidhaveproveneffective.Theseusesofcompositesresult
inanastoundinglossinengineweightofmorethanathousandpounds.
Compositesarealsomoredurablethantheirmetalcounterparts,possessinggreater
tolerance to fatigue and the ability to be molded into approximately three dimensional
shapes ideal for aerodynamics. Composites also resist creep that arise from centrifugal
forcesgeneratedbythefan’shighspeedrevolution,“meaningthattheclearanceengineered
initiallybetweenthebladetipsandthesurroundingducthastobegreaterthanitshouldbe
for optimum engine performance” [23]. Composites also help make engines more fuel
efficientasseenfromCFM’sLEAPenginethatboastsa15%higherfuelefficiency.
Researchintonewandexcitingmaterialshasbeenverybeneficialtotheaerospace
industry.However,manymanufacturersstillfallbackontitaniumduringmaterialselection.
Titaniumisveryversatile,readilyavailable,easytofabricate,veryductile,andhasalowlife
cycle cost, great performance historically, excellent high cycle fatigue (HCF), tensile, and
yieldstrength,lowdensity,andanaturallyregenerativecorrosionresistantprotectivefilm.
Thehighermaterialcost isoffsetbysavings fromlonger lifeandreduction inequipment
maintenanceandaircraftdowntime.Moresignificantly,titaniumhasthehigheststrength‐
to‐weightratiooutofallotherstructuralmaterials.However,thousandsofoperatinghours
leadtodamagesuchashighstrainLCF,FOD(predominantly),wear,andfretting.
‐32‐
While titaniummay be a very reliable and provenmaterial choice,many are still
lookingtocompositesandothermaterial.Compositeshavehighstrength‐to‐densityratios,
stiffness‐to‐densityratiosthreetimeshigherthanaluminum,steel,andtitanium,andhave
yieldedengineweightsavingsofmorethanhalfaton.“Thehighstrengthandstiffnessof
compositematerialscombinedwiththeabilitytotailorthematerialtospecificaerodynamic
loads have led to their increased use in fan blades” [22]. Most composite blades are
reinforcedwithatitaniumleadingedge(LE)andmetalcladding.Thisgivesthemlightness,
improvedstrength,anddamageresistance.Thelowermassyieldslowercentrifugalloads
andstresseswhichcanleadtolongerlife.Thusthereislessdamageandreducednoisewhen
theengineturnsoffandthefanbladesarestillrevolvingatlowerspeeds.
Unfortunately,compositesalsohavelowaerodynamicefficiencywhichisstillbeing
researched.Thisresearchledtothetestingofmetalmatrixcomposites(MMC)whichhave
highstrength,stiffness,andversatilitybutalsoreallyhighcosts.Anothernewmaterialthat
has been researched is hybrid‐metallic material (HMM). “Unlike composite materials,
hybrid‐metallicmaterialsareeasiertotransferamongdesigns,meaningtheyarewell‐suited
to the fabrication of fan blades of any size or dimension” [22]. These structures exploit
certainpropertiesofvaryingmaterialstoimprovestructuralintegrityinspecificareas.They
arecurrentlybeingdevelopedbyPrattandWhitneytoprovidebothweightandstructural
benefits. Unlike composites, HMMs are more versatile and can be adapted to different
designsforfanbladesofanysizeordimension.Theyaremoreresistanttobirdimpactstrikes
andhaveareducedcost.“Researcheffortstopromotethegreaterapplicabilityofhybrid‐
metallicmaterialstofanbladestructuresarerecommended.Nonetheless,significantefforts
havebeenmadetoensurethedurabilityandlongservicelifeofthesematerials”[22].
2.6‐InletDesign
NASAGlennResearchCenterconducteda“SupersonicsProject”undertheInletand
NozzleBranchinconjunctionwiththeSupersonicCruiseEfficiencyPropulsionsgroup.The
team designed a powerful computational tool to perform aerodynamic design and
‐33‐
computationalanalysisspecificallyforsupersonicinlets[7].Thiscodeservesasabaseline
todeterminesupersonic inletgeometryandperformancecharacteristics.Thiscodecould
serveasapowerfulapproachtoallowresearchersandengineerssolveaerodynamicand
propulsion challenges. The code, SUPIN (SUPersonic INlet) Design Code, is capable of
designing and analysis of external ‐ compression, for supersonic inlets of (Mach 1.6‐2.0)
alongwithitsmeasurementsofflowrates,totalpressurerecovery,andinletdrag[7]
2.7‐EngineSelection
Mostenginesonthemarketthatareusedforsupersonicflighttendtoservemilitary
purposes.AircraftsuchastheF‐22,Concorde,andtheF‐11arefewofthemanythatcanfly
atMach1 and faster. Theyutilize turbojet engines equippedwith afterburners for short
burstsofsupersonicthrustduringcombat.Mostsupersoniccraftrequiresuchenginesthat
aresmall indiameter,relatively,andcanreachsuchspeedsquickly.Aspowerfulasthese
enginesare,theyareequallyinefficientcomparedtoenginesusedforcivilandrecreational
aircraft.
Tocompensateforefficiency,aircraftstendtouseturbofanengines.However,most
turbofanscan’treachsonicorsupersonicspeedsunaided.Regardless,thefocusforthetype
of engine that will be selected for themissionwill be towardsmedium to large bypass
turbofans. These engines are efficient and powerful in their own right. They use the air
comingintothefanbypasstohelppropeltheaircraft.
Throughouttheyears,turbofanshaveseenmanyimprovementsfromthematerials
builtintothecomponentstotheshapesofthefan,compressor,andturbineblades.Allofthe
changesareattemptsatcreatingthemostdurableandefficientengines.Tohelptheaircraft
reachsupersonicspeedswillrequireaspeciallydesignedinletandnozzle.
‐34‐
2.8‐NozzleDesign
Preliminaryresearchhasguidedthenozzledesignchoiceinfavorofaconvergent‐
divergentdesign.Thiswillhelpturnsubsonicflowaftertheturbinestageintosupersonic
flowatthenozzleexit.Withsupersonicaircraft,thecustomerwillexperiencelevelsofnoise
thatfarsurpassthoseofmostcommercialaircraftthattravelatsub‐totransonicspeeds.“Jet
noise…seeksadvancedsolutions,especiallyinthecaseofhigh‐speedaircraft”[20].Because
the trend showsa shift toward supersonic travel in theupcomingdecades, technological
advancementsarerequiredtomakesuchtravelmethodsfeasibleanddesirable.Manythings
contributetothenoisesignaturegivenofffromsupersonicengines;however,“jetnoiseis
dominatedbyMachwaveemission,whichariseswhenturbulenteddiesinthejettravelwith
supersonicvelocityrelativetothesurroundingmedium”[20].85%ofthefar‐fieldjetnoise
thathumansaresensitivetocomesfromMachwaves.Otherphenomenacancontributeto
thehighnoiselevels.“Highlevelacousticemissionalsooccursinjetswithstrongshocks,i.e.
in under‐ or over‐expanded jets… [which] can be substantially removed by operating at
pressure‐matchedconditions”[20].
Figure13:SupersonicPlugSpikeNozzle Figure14:SupersonicPlugNozzle
Fortunately,many researchershavebegun to look intoways to correct this issue.
Methodstoreducenoiseemissionsuchasthosethat“enhancethemixingofthejetandthe
‐35‐
surroundingair”[20]comewith“appreciablethrustandweightpenalties.Othersolutions,
liketheInvertedVelocityProfile(IVP)supersonicplugnozzles,oraThermalAcousticShield
haveshownsomeencouragingresultsbuthavenotfoundwideimplementation”[20].Other
methods incorporate changing the properties of the jet streamby surrounding itwith a
secondarystreamoftherightcharacteristicswillinhibitMachwaveformation.Aboveand
belowareimagesofsupersonicplugnozzlesalongwithoneofchevronnozzlepanelsthat
disrupttheMachwavesattheendtoreducethenoiselevels.
Figure15:Nozzlewithchevrons
‐36‐
Chapter3:DesignApproach
3.1‐ProblemSolvingApproach
Torepresenthowtheteamwillapproachthemanydesignchallengeswillrequirethe
useofdifferentmodelingsoftware.TheuseofCFD(computationalfluiddynamics)software
suchasSolidWorks’flowpackage,willhelpmodeltheflowoftheairenteringthe“cold”parts
ofourengine(i.e.inlet,fan,compressoretc.)aswellastheflowalongthefuselage.These
modelswillgeneratekeyresultsthroughcalculationsusinggivenparameterstorepresenta
prediction forhowa full scale componentwill behave realistically.The figureswill yield
resultsthatwillbeusedwithinfurthercalculationsandchartstoshowifthechallengeswere
metwithin the desired 5%margins. Theywill also help aid in the design of the engine
componentsafterthecombustor(i.e.turbineandnozzle).
Another software to possibly be used for the completion of the project will be
NumericalPropulsionSystemSimulation(NPSS).NPSSisasimulationprogramthatis“block
oriented”andcanbeusedforengineeringdesignandtosimulateaerospacesystems.This
programworksbytakingthedifferentelementsspecifiedbytheengineerandtherespective
technicaldatathatdetailstheirindividualperformanceandsolvesthesystem.Theprogram
takestheinputtextfilesfilledwithcodetypedinC++languageandlaunchesthemviathe
systemcommandwindow.Forthisproject,NPSSwillbeusedasacomputationalmodelof
theengine’sparametriccycleanalysis.
Tomodelandanalyzethebehavioroftheturbomachineryinsidetheengineandfind
certaindataparameterssuchasthetemperatureandpressureatvariousstages,theteam
canpotentiallyusetheprogramAxSTREAM.AxSTREAMisasoftwarepackagethatisused
forarepresentativedesignofthecompressorandturbine,andalsotosolvethermodynamic
calculationsofindustryturbomachineryforbothonandoff‐designoperation.Givencertain
initialparametersfortheinletandtheoutlet,theprogramcanthenperform1D,1D/2D,and
3DcalculationsthatencompassCFDanalysestocreateamodelforthedifferentcomponents.
Thissoftwarewillhelpvalidatecertaindesignchoicesmaderegardingtheengineandits
‐37‐
components, and itwill also serve to revealparameters thatwouldhavebeenotherwise
unknowntothegroup.
Throughout majority of the project, Microsoft Excel was used for the numerical
calculations.Havingtoperformparametriccycleanalysis,besidesMatlab,Excelwouldbean
easierprogramtouse.UsingExcelalsohelpedtocorrelatedatafromdifferentsheetsand
workbooks to create plots for the necessary trade studies. Excel also helped highlight
different values and data points from the collection of historical data gathered on the
hundredsofenginesusedinindustry.TransposingthedatatoMatlabisstillaviableoption
andmaybedoneforfuturenumericalsimulationsandcalculations.
3.2‐GanttChart
Theflowofworkinthisprojectiscrucialgiventhestrictdeadline.Thus,toensure
tasksarecompletedontimeandprogresswasmade,aGanttchartiscreated.TheGanttchart
provedusefulforsettingmaintasksandgoalstocomplete.TheGanttchartalsoprovidesa
visualontheprogressmadeontheprojectthroughouttheentiresemesteritwasworkedon.
Within each respective task, a weekly progress report was made. Specific tasks were
delegatedtoensureprogresswithineachgoal.TheGanttchartwhichwasusedisprovided
below.
‐38‐
Figure16:ImplementedGanttChart
3.3‐Flowchart
Inordertocompletethisproject,asystematicflowchartwasgeneratedto
characterizethedesignprocess.Utilizingsimilardesignflowsofaircraftdesign,thesame
couldbeusedfortheengineandvariouscomponentsofthisproject.Theflowchartshown
belowdescribestheiterativeprocessusedthatallowedmultipleversions,optimizations
anddesignsfortheoverallproject.Byutilizingtradestudies,sizingconfigurationsand
designtrades,afinalizeddesignwasconcludedforthisproject.Although,future
refinementscanalwaysbemadetothisproject,deliverablesareimportantthusthisflow
chartaccountsforthat.
‐39‐
Figure17:DesignFlowChart
3.4‐Resources
KennesawStateUniversityoffersavastnumberofresourcestoensureacomplete
project.ThefacilitiesontheMariettacampusofKennesawStateUniversityoffersmultiple
avenuestoexploreandcreatemodelsandobservecharacteristicsofflight.Alistofthemis
providedbelow.Inadditiontoresourcesoncampus,alistofpossiblesponsorsisprovided
whencompletingfutureworkandpossiblepartnershipswiththeuniversitytoobtainaccess
tocertainlaboratorymaterialsorsupplies.Lastly,alistofhardwareandsoftwareavailable
incompletionofthisprojectisgeneratedwhereaccessisreadilyavailable.
Facilities:
FluidDynamicsLaboratory
ControlsandVibrationsLaboratory
3DPrintingLaboratory
FlightSimulatorLaboratory
ArchitectureWoodshop
PossibleSponsors:
‐40‐
1. KennesawStateUniversity
2. GeorgiaTechResearchInstitute
3. LockheedMartin
4. Spaceworks
5. NorthropGrumman
6. CATIA
7. ANSYS
AvailableSoftware:
1. Solidworks
2. ANSYS
3. MATLAB
4. SIMULINK
5. MicrosoftOffice
6. Latex
7. AxSTREAMbySoftInWayInc.
8. NumericalPropulsionSystemSimulation(NPSS)
9. GasTurb12
Hardware:
1. 3DPrinter(s)
2. COXparts(Commercialofftheshelf)‐McMasterCarretc.
3. WindTunnel
‐41‐
Chapter4:EngineeringAnalysis
4.1‐ParametricCycleAnalysis(PCA)
To determine if the baseline engine was a suitable engine, the team performed
parametric cycle analysis. Research was conducted to find the input values that were
required for the calculations. For the values that were not given through research,
assumptionsweremade from the trendstudiesof similarengines.After the inputswere
found, anExcel sheetwasdesigned that incorporated thePCAequations (1) ‐ (45) from
Elements of Propulsions [11]. After the program finished, the propulsive and thermal
efficiencies were calculated and found to be 98.53% and 51.46%, respectively. These
efficiencieswouldyieldanoverallefficiencyof50.7%.Thiswasdeemedacceptablebecause
itwasclosetotheefficienciesoftypicalhighbypassturbofanengines.Belowaretheinputs,
outputs, and equations used for the PCAprogram excluding any afterburner parameters
giventheirabsencefromallenginestested.
‐42‐
‐43‐
‐44‐
‐45‐
‐46‐
After the initial PCAprogramwas completed, the teamdecided to do one for the
candidate engine. By using the results from thewave drag calculations alongwith input
valuesfromindustry(e.g.GEGenXfanratioandbypassratio)dependingonwhatengine
parts were used for the team’s design. Because the new design was performing under
different conditions, the program yielded different results. The propulsive and thermal
efficiencieswere61.8%and30.9%respectivelytoyieldanoverallefficiencyof19.1%.The
latterprogram involvedengineperformanceunder theAIAAconditionsset in thedesign
characteristics,whilethefirstwasundertypicalmissionconditionsforcurrentturbofans.In
AppendixXarefiguresoftheExcelprogramcreatedforthePCA.
4.2‐SupersonicWaveDragCalculations
Modeling wave drag is conducted both numerically (analytically) and
computationally for initializing baseline supersonic wave drag calculations. In order to
determineabaselineinviscidwavedrag,variousprojectedareasoftheaircraftmainframe
body such as; fuselage, wings, and control surfaces are constructed in mathematically
relationships.EstimatedfromEulerdifferentialequation,eachcomponentissimplifiedto
achieveboundsonobtainingminimumdrag[21].Equation(1),SlenderBodyWaveDrag,
describes the fuselage main body frame in integrating along for slender bodies with
considerablyhighfinenessratios.
SlenderBodyWaveDrag
(46)
Theminimumwavedragestimation is crudeandsimplistic formula thatprovides
projected area of drag due to supersonic thin airfoil theory. Due to air density
compressibilityeffectsatsupersonicspeeds,theapproximationofdragamonganairfoilis
explored.Equation(46),Vrepresentsthesonicvelocityofairflow,lrepresentsthelengthof
theairfoil,ρisthedensityofair,andUdisplaysthedynamicpressure.
‐47‐
MinimumWaveDrag
(47)
Volume‐DependentWaveDragusestheestimatedwavedragofawing.Specifically
referencedinJ.H.BSmithtext,hederivestheexpressionforthevolumedependentwave
dragforanellipseshapeshowninEquation(47).Intheequationtismaximumthickness,b
isthesemi‐majoraxis,andaisthesemi‐minoraxis.
Volume‐DependentWaveDrag
(48)
UsingEulerprinciple,R.T.Jones’expressiondescribesthemathematicalrelationship
forlift‐dependentwavedrag[2].Itconsideredtheellipseofthesamearea,S,andlength,las
seeninEquation(49)
LiftDependentWaveDrag
(49)
Usingthegoverningequationsestimatingwavedragreferencingequations1through
4,anumericalbaselineestimationofwavedragcanbecalculated.Thedesignchallenged
aircraft will explore a trade study of total drag and the number of engines needed to
overcometheresistanceforce.DisplayedinFigure18aresamplecalculationsofestimated
supersonicwavedragatMachconditionsof1.3,1.6,and1.8.
‐48‐
Figure18:Numericalandanalyticalwavedragestimationforhighspeedsupersonic
compressibleflow
‐49‐
Figure18:Numericalandanalyticalwavedragestimationforhighspeedsupersonic
compressibleflow(continued)
‐50‐
4.3‐InletDesignCalculations
CFDonsupersonicinletpressurerecovery
Computational FluidDynamicAnalysis is conducted to validate and test two inlet
designconfigurations.Theseconfigurationsareanalyzedtoexplorethepressurerecovery
tomaximizeefficiency for the fanandengine.Asseen inFigure19, thespikedesignCFD
analysisshowsagreaterpressurerecoverythanthedoorpanelsinFigure20.
SubsonicMilSpecPressureRecoveryCalculation
Mil.Spec:M>1:pt2/pt0=ni*(1‐.075*[M‐1]^1.35)(50)
M>1:pt2/pt0=ni*(1‐.075*[M‐1]^1.35)
=3.994095965
Figure19:SupersonicspikeCFDanalysisforinletdesign
‐51‐
Figure20:SupersonicpanelchannelCFDanalysisforinletdesign
Mil.Spec:PressureRecovery
M>1:pt2/pt0=ni*(1‐.075*[M‐1]^1.35) (51)
=3.292803708
Duringtheoptimizationphase,adesigntradestudycanbeviewedinAppendixB
InletDesignAnalysisTradeStudies.ThefinalselectiondisplaystheCFDresultantanalysis
inFigure21a,b,andc.
(a)
(b)
‐52‐
(c)
Figure21:SupersonicextendedandoptimizedpanelchannelCFDanalysisforinletdesign
(a)Pressure(b)MachNumber(c)Velocity
4.4‐InitialWeightCalculations
Initialsizingcalculationsaredonetodeterminetheemptyweightaswellasthe
take‐offweightoftheaircraftdesign.Thesecalculationsforthisparticulardesignarebased
onempiricalequationsandhistoricaldatafoundinsimilaraircraftwithsimilarproperties.
MissionProfileoftheAircraft
Figure22:Themissionprofileoftheaircraft
‐53‐
EstimateofTake‐OffGrossWeight
Calculatingtake‐offweightusesthefollowingequationusingtheweightofthe
passengersandtheweightofthepayload.FromtheAircraftDesigntextbook[10],mission
segmentweightfractionswerefoundusingTable3.2.
Thefollowingequationisusedtocalculatedanapproximatedgrosstake‐offweight.
(52)
Thefuelweightfractioniscalculatedusingthefollowingequationinregardstothe
missionsegment.
. (53)
Theemptyweightfractioniscalculatedusingtheequationbelow.Sincethedesign
willbeinsupersonicconditions,themostapproximatevaluethatismostsimilarwouldbe
amilitaryjetfighter.Thus,valuesforamilitaryjetfighterwereusedintheemptyweight
fractioncalculation.
. . (54)
UsingtheBreguetrangeequation,thiswasusedtocalculatedtheweightfractionfor
climb.
(55)
‐54‐
Byusingtheseequations,anapproximatedweightwascalculatedusinganiterative
process.Thecalculatedemptyweightoftheaircraftwasfoundtobeapproximately
138,482.04poundsandthetake‐offweightwasfoundtobe317,432.72pounds.Adetailed
calculationcanfoundintheAppendixI.
Figure23:ComputerAidModeldemonstratingcruiseclimbpriortosupersoniccruise
mission.
4.5‐ComputationalFluidDynamics
SolidWorksisusedtoperformtheCFDanalysesforvaryingpartsoftheaircraftand
engine. Itwas selectedas the team’s sole sourceofCFDanalysesdue to easeofuse and
commonfamiliarity.Dependingonthepartsexamined,certainkeyparametersweresolved
for.Forexample,whenstudying the flowthrough thenozzle, thevelocity,Machnumber,
pressure,andtemperaturewerethekeyaspects.Thesetestswouldenlightentheteamabout
howhardthenozzlewouldexpeltheflow,ifthejetcouldreachMach1.6‐1.8at55kft,and
howmuchnoisetheenginewouldproduceviatheexitvelocity.SeeninAppendixA,B,and
CarevariousCFDanalysesperformedonsomeofthecomponentsoftheaircraft.
4.6‐ComputationalMethods‐PARA
PARAisasupplementalpieceofsoftwareprovidedbyAIAAthroughtheElementsof
Propulsion text by Jack D.Mattingly. PARA is a useful software package for this project
because it is capable of conducting simultaneous equations involved in parametric cycle
analysis.Withthisability,varioustradestudieswereconductedonthebaselineengine.For
this program, input data is required to solve for the iteration variables desired. In this
program,asetofinputdatawasprovidedbyAIAA.PARAallowsforathroughcomparison
‐55‐
ofvariedinputvalueswhichnotonlytabulatesthedatabutalsographsit.Theinputvalues
aswellastheoutputdeliverablesareseenbelow.
Figure24:Inputparametersintotheprogram
TheparametersplacedinsidethePARAprogramareplacedshowninFigure24.The
designvaluesareshownonthebottomleftcorneroftheinputwindow.Thesevaluesare
designatedfortradestudiesandareusedtodeterminethecombinationofparametersthat
willmeettheneedsofthedesireddesign.
‐56‐
Figure25:OutputvaluesfromtheprogrambasedoniteratedLPCPressureRatio
Figure25isanexampleoftheoutputresultsthatcomefromthePARAprogram.The
results show the iterations on the LPC pressure ratio. For each iteration, values for the
thermalefficiency,propulsiveefficiency,fueltoairratio,andmanyotherenginevaluesare
calculated.ThePARAprogramispowerfulinconductingmultipletradestudiesonmultiple
parameters.AnexampleofonetradestudyisshownwithFigure26.
‐57‐
Figure26:OutputvaluesfromtheprogrambasedoniteratedLPCPressureRatio
InFigure26,theoutputvaluesfromtheLPCcompressoriterationsallowedforplots
ofvaryingresults.ForFigure26,theoverallefficiencyoftheenginecanbeobservedwith
regardstotheLPCpressureratio.AmoredetailedanalysisofplotsareseeninAppendixD.
InAppendixD,carpetplotsweregeneratedtoplotmultiplesetsofdatainonegraph.The
carpetplotswillaidinrefiningtheoverallenginedesign.
4.7‐ComputationalMethods‐TURBN
TURBN is another supplemental software provided through the Elements of
Propulsion text by Mattingly. It is valuable because with it, one can solve simultaneous
equations concerning turbine performance. However, the software has some constraints
withcertainparameterssuchaslimitationsforthemeanradiusandthetemperature.But
withit,simulationswereabletobedoneonasimilarengine.Toinitiatetheprogram,input
‐58‐
variablesmustbesubmittedforthesoftwaretosolveforthespecifiedvariables.Theinput
dataisprovidedbyAIAAwithassumptionsalsobeingmadeforcertainvaluesbasedonthe
software’ssuggestionandthetext.Belowaresamplecalculationsdonefromtheprogramfor
thefirststageoftheturbinealongwithachartgeneratedshowingthetrendsofdifferent
variablesinrelationtoothersandthevelocitytrianglefortherotorandstatorblades.
Figure27:TURBNStage1calculations
‐59‐
Figure28:TurbineBladeProfile
Figure29:TableofTurbineConstraints(AngularVel.vs.MeanRadius)
‐60‐
Chapter5:ResultsandDiscussion
5.1‐HistoricalData
Theensure feasibility in thedesigndecisions forcandidateengines forsupersonic
transport,considerationsneededtobemadeinrelationtoexistingengines.Researchwas
done on existing engines to determine their respective technical specifications. Through
varioussources,acompiledtabulated listofvaluesoftechnicalspecificationsforexisting
engineswas created. Specifications tabulated include:Thrust, SpecificFuelConsumption,
Overall Pressure Ratio Fuel Pressure Ratio, Bypass Ratio, Thrust at Cruise, Specific Fuel
ConsumptionatCruise,CruiseSpeed,CruiseAltitude,andotherparametersweretabulated.
Amoredetailedviewofthesevaluescanbeseenintheappendix.
Given that the information for each engine is provided, plots were generated to
determinehistoricaltrendsbasedonenginetype.Multipleplotsweregeneratedusingvalues
found specific to each engine. Parameters for each of these engineswere compared and
plottedtoobtaintrendsthatwouldallowdesigndecisionsforcandidateengines.Toobserve
thedifferencesbetweeneachengine,theseplotscanbefoundintheAppendixH.Usingthe
tabulated data, reasonable values can be determined for each engine. Based on the
requirementsprovidedbyAIAAandNASA,sounddecisionscanbemadeforeachparameter.
The process for selecting design parameters will point to the generated plots from the
historicaldatatoaligndesignselectionswithinareasonablerange.
5.2‐TradeStudyEngineDesign
Togeneratetradestudiesfromthetabulatedhistoricaldata,acomparisonwasmade
between two varying specifications. Using these respective parameters, trends can be
observed.Forthethrustplots,thepointswereextractedfromthehistoricaldataandplotted
againstothervaluestodeterminethetrendsforbothmilitaryandcommercialaircraft.For
‐61‐
efficiency plots, baseline valueswere selected and kept consistent. To observe changing
effects,asingleparameterwaschangedtoobservetheefficiencies.Thermalandpropulsive
efficienciesweredeterminedforeachengine.Giventhevaryinggeometriesofeachengine,
valuesthatwerekeptconstantwere:
Cruiseconstantparameters:
‐ Altitude
‐ Airspeed
‐ Temperature
‐ Nozzleandcoreexitvelocities
‐ Speedofsound
‐ Fueltoairratio
These listedparametersarethenusedinthecorrespondingefficiencycalculations
locatedintheAppendixI.Thedatafromourgraphsarewithrespecttovaryingbypassratio,
thus,thereisaconstantincreaseinrelationtooverallefficiencyseenintheappendix.
5.3‐DiscussionofHistoricalData
Tradestudieswereconducted forbothmilitaryandcommercialaircraftand their
respectiveengines.BycomparingthrusttoseveralotherparameterssuchasOPR,TSFC,and
BPR,differenttrendscanbefound.AsseeninAppendixI,thrustisdirectlyrelatedtothe
OPR, displaying a linearly increasing trendline. Thismakes sense since the difference in
pressureisacontributingfactortohowfastanaircraftcantravel.
Avarietyoftrendscanbeobservedfromthegeneratedplots.Thesetrendsareuseful
whendetermining theparameters for selecting values for the final design of the engine.
Basedonthetrendsobservedfromtheplotsgenerated,avaluewithintheplottedrangecan
beselected.Foraspecificdesignparameter,anassociatedplotandvaluecomesasaresult.
Giventhedatathroughmultipleaircraftengines,itprovidesperspectiveontheoverallstate
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ofjetenginetechnology.Notonlycanadecisiononparametersfortheenginecanbemade,
butifacertainparameteristargeted,anassociatedsetofdatawillcomeasaresult.Thus,
throughbackloggingofallpreviouslyplottedengines,adeeperinvestigationcanbedone.
For thatselectedparameter,anengine isassociatedandanalysiscanbemadeonengine
geometries,numberofcompressorstages,andotherparameterscrucialtoenginedesigncan
beextracted.Thedepthofthehistoricalplotswillaidinfurtherresearchandinvestigation
foroptimizationofthefinalenginedesign.
Asaresultofgeneratinghistoricalplotsforthegivenengines,abaselineparametric
cycleanalysisprogramwasalsogenerated.Duringthedurationofprogressmadeforthis
project,theparametersusedtocalculateandgenerateefficiencyplotsalsostreamlinedthe
processfordesigninganengine.Throughthecompileddata,furtheranalysiscanbemade
forvariousdesignchangeslater.Duetotheiterativenatureofparametriccycleanalysis,by
generating the extensive and involved program for calculating overall efficiency, the
processesneededforfurtherinvestigationandoptimizationofthedesignedengine.Asthe
challengeofdesigninganenginebecomesmore involved, throughthedesignedprogram,
valuescanbechangedontheflyforrefineddecisionmakingandcomparisonofparameters
chosen experimentally to compare results such as efficiency, TSFC, and turbine inlet
temperature.
Chapter6:Prototype
6.1‐ComponentDesign
Forthefandesign,onemodelingthefanfortheGEGenx‐1Benginesisused.Thefan
hasabypassratioof9andafanpressureratioof2.25.Thediameterofthefanis70.3inches.
Itismadefromcompositematerialandforthesakeofthedesignshouldbehollowedoutto
reduceweight.The leadingedgewillbemadefromtitaniumforreasonsdiscussed inthe
literaturereviewsection.Belowarepicturesofthefanbladeandthefanhubassembly.
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Figure30:EngineFanBlade Figure31:EngineFanHub
Thenextpartoftheenginethatwasdevelopedusingmethodsotherthannumerical
analysiswasthenozzle.Usingthebelowequationsandthedesignrequirements,theteam
wasabletodeterminewhatexittothroatarearatiowasneededforMach1.6flight.
Figure32:NASACalculationsforNozzleBehavior
Calculationssuggestanarearatioof2.16andanozzlepressureratioaround9.25.
Thesecalculationsalongwithresultsfromsimulationsforthethermodynamicsinvolvedin
theturbomachinerywillhelpcompleteanozzlesuitableforthemission.AfterCalculations
werefinisheddifferentdesignsforthenozzleweretestedtoconfirmthecalculationsusing
SolidWorksandCFDanalyses.SeeAppendixCfortheCFDanalysisresults.TheCFDshowed
thatboththeconvergent‐divergentnozzleandtheplugnozzledesignwereabletoachieve
‐64‐
Mach1.6.Because theplugdesignwasmorereliable (consistent flowbehavior) than the
convergent‐divergentnozzlealsodepictedinAppendixC,itwaschosenforthefinaldesign.
TheaircraftmustalsoreachspeedsofMach1.8.Tocompensateforthis,theteamchoseto
gowithavarying‐areanozzledesigntoincreaseanddecreasetheexitareaaccordinglyto
achievewhatever speed the aircraftwill require throughout themission.BelowareCAD
modelsofthefinaldesignoftheVaryingPlugNozzle.
(a) (b)
(c)
(d)
Figure33:Modelsof:nozzle(a),plugdesign(b),fullyopenednozzleexit(c),fullyclosed
nozzleexit(d)
The model was created using some parts and methods found online in order to
demonstratehowthenozzlepanelscanchangearea.Thepanelswillideallybetestedtosee
ifaddingchevronscanhelpdecreasethevelocityoftheexhaustjet.Preliminarytestsshowed
exitvelocitiesupto4,000ft/s incertainareasasseenintheCFDanalysisinAppendixC.
However,thiswasnotconsistentwiththemaximumMachnumbercalculatedwhichinsists
thatanerroroccurredduringtheanalysis.Otherideasconsideredweretoaddathermal
‐65‐
acoustic shield and chevrons at the end of the panels to see how thatwould change the
velocityresults.
6.2‐AircraftModel
Thedesignofthefuselagewellundergoesvariousdesignconfiguration.Insupersonic
flow,everyaspectofthevehiclemustbeutilizedtomaximizethrust,aswellasreducingdrag
andspecificfuelconsumption.Airfoilhavestronghistoricaldatabaseandarchivestoaccess
airfoil characteristics. Fuselage have a small selection of general shapes that base of the
cylindricalgeometry.Inthenextvehicledesignchallenge,amathematicaloval‐conicalshape
will be modeled to integrate the high factors of aerodynamics and maintain feasibility
spacing for passengers. The design selection combines various combinations of sized
fuselage sections. This desired design will to maximize passengers in specific business
economysections.
Figure34:Isometricandprofileviewofsupersonicprototypeaircraft
‐66‐
Duetosupersonicshockwaves,thefuselagewillhouseallitspassengersandcrew
nearthefrontofthevehicle.Thisallowstheenvironmentalcontrolsystemstobestoredin
therearoffuselage.Thispromotessaferconnectionsfortheenergysupplytothemixedflow
turbofanengines.Also,astheaircraftappliesanenormousamountofthrusttotheengines,
loudvibrationsaremorepronetoresonatethroughthefuselage.Havingtheplacementof
engines further back reduces the amount of vibrations the passengers will experience.
ShowninFigure35,theprofileloftviewsofthedevelopmentalsupersonicprototypemodel.
Figure35:ComputerAidModelbodyloftingprocessofsupersonicaircraftvehicle
Forthedesignedtargetedgoal,aseriesofconfigurationsofaircraftmodelsareexplored.The
first design focusedon a simplistic, yet effectivedelta trianglewing shown inFigure36.
Design1hasalargeverticalstabilizerinordertocounteractaggressiveunwantedmoments.
Figure36:Design1conceptwithdoubledeltastraightwinggeometry(isometricandrightsiderespectivelyprofiles)
Withfurtheranalysisandnumericalcalculation,anoptimizationphaseisapproached
inordertomeetweightrequirements.TheweightfromDesign1exceededthemaximum
‐67‐
requirements. Thus, Design 2 aims to reduce weight by trimming area from the wing
geometry.AsseeninFigure36,thewinggeometryisnowinspiredandintegratingadouble
deltawingconfiguration.
Figure37:Design2conceptwithdoubledeltastraightwinggeometry(isometricandright
siderespectivelyprofiles)
ThethirditerationisanintegrateddesignusingcuesfromDesign1and2byreducing
bothweightanddrag.Anextensivecomputational fluiddynamicanalysis isconductedto
understandthecompressibleeffectsofthevehicle.AppendixAdisplayscomputationalfluid
resultsforDesign3.
‐68‐
Figure38:Design3conceptwitharceddeltastraightwinggeometry(isometric,front,
rightsiderespectivelyprofiles)
Duringthephysicsflowsimulations,theobjectiveistounderstandtheflowfieldasit
interactswiththemailbody.ThelessonsfromDesign3,itimprovesandreducesthedrag
coefficient as well asmaintains stability in flight shown from the computational model.
Figures39showstheresultantMachnumber,pressureandtemperaturecomparison.
(a)
‐69‐
(b)
(c)
Figure39:Design3conceptwithcomputationalfluiddynamicmodelmeasuring(a)Mach
number,(b)pressure,and(c)temperaturerespectively
Afterextensivesimulationbothnumericallyandcomputationally,thedesignofthe
vehiclebecomesmorematuredovertime.Fromengineinletandengineanalysis,the
geometryofthedesignrequirestheinletlengthandwidthtobeincreasesapproximately
by15%foroptimalefficiency.Fortheresizingoftheinlet,configurationofengine
placementisconsideredintwolocations.ThefirstorientationdepictedinFigure40,shows
ductslocatedbothaboveandbelowthevehicle.Incomparison,Figure41demonstrates
bothductsandenginesunderneaththefuselage.Thiseasesmaintenancecapabilitiesand
allowscleanstreamlineairflow.Inretrospect,theaircraft'scenterofgravityshifts
backwardrequiringmorestructuralsupportandlongerlandinggears.
‐70‐
Figure40:DesignconceptwithenginelocationconfigurationforOrientation1(oneengine
above,withonebelow).
Figure41:DesignconceptwithenginelocationconfigurationforOrientation2(two
enginesbelowfuselage)
6.3‐EngineModel
Acomprehensiveassemblyofeachmaindrivingcomponentofthesupersonicpower
plantismodeledtotherequiredsizeshowninFigure42aandb.Thepropulsionsystemisa
highbypassturbofanenginewithbaselinecomponentsinfluencedfrombothmilitaryand
commercialvehicles.Theengineiscomposedofcompositesweptfanbladeswithadiameter
of70.3inches.Thecompressorhas11stageswith10stagesofstatorblades.Theburner,or
alsoknownascombustionchamberismodeledfromtheTAPSIICombustorCleanProject
(CLEEN).
‐71‐
(a)
(b)
Figure42:Designconceptforsupersonicenginepowerplant(a)sideprofile(b)front
profile
6.4‐InteriorDesignConfiguration
A design study was conducted to identify possible seating configurations for the
interiorof theaircraft.Considering thisaircraft isdesignatedasabusinessclassaircraft,
accommodationsmustbemadetoensureasenseof luxuryinthecabin.Twoapproaches
weremade in terms of identifying the seating desired. One approachwas to implement
standardseating found ineconomyplusseating found inthecurrentstateofcommercial
aircraft. The other approach was to utilize a more modern and private class seating
configuration. In addition, the various seating configurations can be utilized with each
seatingarrangement.Usingthetwostylesyieldaslightlyvaryingseatingarrangementinside
thecabin.Thedifferentconfigurationsareshowninthissection.
‐72‐
StandardConfiguration
Figure43:Standardconfigurationlayout
Figure44:Sideviewofstandardseating
‐73‐
Figure45:Overheadviewofstandardconfiguration(Left),
Figure46:IsometricView(Right)
‐74‐
Figure47:Detailedviewofseating[28]
Figure48:Detailedviewofseating[28]
‐75‐
LuxuryClassConfiguration
Figure49:Luxury/PremiumEconomySeating
Figure50:Sideviewofseating
‐76‐
Figure51:Overheadviewofconfiguration
Figure52:IsometricView(BottomRight)
‐77‐
Figure53:Detailedviewsofmodernandupdatedluxuryclassseating
‐78‐
The standard seating configuration of this aircraft will seat over 100 passengers
comfortably.Theonlydownsidetothisconfigurationisthatitonlyoffersverybasicseating
withminimal features for a business class seat. One aspectwith themore basic seating
configuration is that, depending on the target, if more passengers are desired then the
commercialstandardconfigurationcanbeutilized.Although,anegativesideeffectsofthis
configuration is that it does not offer luxury or first class amenities for passengers. If
additional seats were added to the existing configuration it would seat 132 passengers
comfortably.
Luxury/PremiumEconomyseatingallowsfor themaximumamountofpassengers
onboardtheD3aircraft.Usingatwobytwoseatingconfiguration,multiplepassengerscan
beaccommodatedontheaircraft.Abusinessclasssuiteseatingoptionisalsoavailablefor
implementationintheaircraft.Eachpremiumeconomyseatfeaturescontrolsonthearm
rest.Thepremiumeconomyconfigurationseats132passengersusingthetwobytwoseating
arrangement.Theseatscanalsoactasabedplatformbyextending theseatout.Further
studiescanbemadeontheinteriorseatingconfiguration,althoughthesemodelswillassist
indescribingtheoveralldesignofthisaircraft.
‐79‐
Chapter7:Conclusion
Theinitialdesignoftheaircraftandenginehavebeencreated.Usingnumericaland
computationalmethods,thedesignshavegonethroughverificationoffeasibilityandvalidity
indesignchoices.Fromthetradestudyitemsfortheengine,performancecalculationsand
simulationswerecreated todetermineaprototypephase for theenginedesign.Through
simulations,variousconditionswereselectedtoobservethecharacteristicsoftheaircraft
throughSolidWorks.
Afterliteraturereview,aircraftdesignswerealsoselectedbasedonadesignmatrix
andanobjectiveTOPSISanalysis.Enginedesignparametersandgeometrieswerestudied
andimplementedintheiterativedesign.Advancedcalculationsfornumericalmethodswere
foundthroughvariouspublicationsandtextbooks.Toensurevalidcalculations,supersonic
equationsandstudieswerereviewed.Athoroughstudyofinletdesignswasalsoreviewed
andsimulatedusingSolidWorks.Then,throughexistingenginesandnozzledesigns,further
reviewsallowedfurtherinvestigationsonotheralternativesalongwithsimilarselectionsto
implementintheworkingdesign.
Throughtheengineeringanalysis,ParametricCycleAnalysiswasconductedonthe
baselineengineandatradestudywascompletedusingcomputationalmethodsusingthe
PARA and TURBN programs provided by AIAA. Supersonicwave drag calculationswere
foundafterextensiveresearchonpreviouspublicationsandpapersinthesamefield.Forthe
aircraftandengine,supersonicwavedragguidedmanyofthecomponentselectionsforthis
project.Inletdesigncalculationswerealsofoundandcreatedtodetermineasuitableinletto
slowdownthefreestreamairenteringthecoreandbypassoftheengine.Byconductingthis,
itwillreducethestressesonenginecomponentsandensureasmoothtransitionofairfor
the overall engine. CFD was conducted on the various designs for varying supersonic
conditions.Ofthesesimulations,theinlet,aircraft,andenginecomponentsunderwentaCFD
simulationtoobserveeffectsonpressure,Machnumber,temperature,andvelocity.
‐80‐
The prototypes for this project include component design, engine models, and
interior design configurations for the finalized aircraft. The component design involves
generateddetailedmodelsofthefan,inlet,compressor,turbineandnozzle.Fortheaircraft,
variousconfigurationsusingvaryingaircraftpropertiesandgeometriesaregenerated. In
addition, detailed CFD was conducted on the overall aircraft design. The interior
configurationof theaircraftwascreatedusing twovaryingstyles,oneapproach involves
usingasimilarformatandseatofstandardcommercialairlinersandthesecondapproach
involves using a moremodern design. Each configuration seats at least 100 passengers
althoughthefirstapproachseats100passengersexactlywiththetrade‐offoflackingany
luxuryfeatures.Bygeneratingseatingconfigurations,itallowsavisualonthefuselagedesign
aswellasconsiderationsforspaceofpassengersinside.
This project involves various trade studies and designs. A finalized model of the
aircraftwithvariousengineplacementconfigurationsaremadetoaccommodatetheengine
sizeaswellastoobservetheeffectsofcleananddisturbedairontheaircraft.Totakethis
projectfurther,3Dprintsofthecomponents,aircraft,andenginecanbemadetoobserve
manufacturingprocessesthecomplexityofmanufacturing.Also,3Dprintscanalsobeused
inawindtunneltoobservetheeffectsofdragontheaircraft.Weightreductioninvarious
componentscanbemadeaswellasacousticlevelsofthisdesigncanalsobegeneratedto
furtherrefinethedesign.Newtechnologiesarealwaysadvancingandtheimplementationof
theseinthefinalizeddesignshouldbetakenintoconsideration.
‐81‐
Chapter8:FutureWork
Givenmore time to develop the design, further exploration of different fan blade
airfoilsandtechnologiescanbedone.Givenhowfarresearchershavecomenowandwhere
theyareprojectedtogo,thepossibilitiesareendless.Moreexplorationofceramicandmetal
matrixmaterialalongwithconductingmoreteststoseewhichmaterialswouldbestfiteach
component could be done. Another area to expand uponwould be the hub assembly. A
common concern found during initial research was finding better ways to connect the
varyingcomponentstoachievemaximumweightsavingsandefficiency.
TryingtodevelopneworenhancecurrentstudiesontheTAPSIIleanburncombustor
could also be initiated. The technology seems very promising and will propel the low‐
emissionschallengeforwardtoboundsyetforeseen.Beingfairlynewtechnologynotmuch
publicknowledgewasfoundonitinawaytoseehowitwouldperformwithvariousengines
andengineconfiguration.
Concerningtheturbineandcompressor,unfortunately,timewasspentstudyingthe
effectsduetolimitedtimeandresources.However,thatdidnotstoptheteamfromwanting
tocarefullydevelopananalysisplan todeterminewhatwouldbe thebestgeometryand
configuration to create an efficient flow through the core of the engine. With our low
efficiencyofabout19%, thereseems tobe reason tobelieve thatmorecouldbedone to
improvethepropulsiveefficiencythroughthesetwocomponents.
Withthenozzle,therearenumerousapproachestonoisereduction.Furtherresearch
canbemadetodeterminethenoiseeffectsonhumansbyexitvelocitycouldbedeveloped
and studied upon. Each method would require different geometries and could result in
weightgains,soimprovinguponcurrentnoisereducingmethodscouldbeverybeneficialto
theindustry.
Concerning emissions, the engine can be designed to lower nitrogen oxide (NOx)
emissions.Emissionlevelswillbeintermsofthetotalmassoftheemissioncreatedduring
acertainlanding‐takeoff(LTO)operationalcycleperkilonewtonofratedtakeoffthrustat
‐82‐
sea level (std). For next generation supersonic aircraft, NOx emissions contribute to the
deterioration of the stratospheric ozone because they cruise at higher altitudes. A NOx
emissionsindexof5g/kgfuelduringcruiseisthedesignrequirementforoursupersonic
engineforfurtherdevelopmenttofulfiltheAIAArequirements.
Afterallofthestudiesandanalyseswouldbedone,theteamwouldliketoexplore3‐
Dprintingandsupersonicwindtunneltestingoftheaircraftfuselage,inlet,nozzle,andany
appropriatecomponentthatcouldbedonetogatherreal‐lifetestresults.Thisalongwitha
systemanalysis of the entire engine could beperformed to showhow the enginewould
functionrealistically.Afterthetestsaredone,allofthematerialdataandweightscouldbe
gathered togiveareal‐timerenderingofwhatanaircraft suchas theonecreatedwould
require to be used in industry. This would include pricings, maintenance requirements,
suggestedmissions,etc.
‐83‐
Acknowledgements
KennesawStateUniversityo DepartmentofIndustrialandSystemEngineeringo AdeelKhalid,Ph.D.o ChristinaTurner
AmericanInstituteofAeronauticsandAstronautics
NationalAeronauticsandSpaceAdministration
‐84‐
References
[1]Welge, Harry R, et al.N+2 SupersonicConceptDevelopmentand Systems Integration .
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[2] Coen, Peter. ARMD Strategic Thrust 2: Innovation in Commercial Supersonic Aircraft.
NASA,24May2016.
[3]WhatIsNumericalPropulsionSystemSimulation(NPSS®)?SouthwestResearchInstitute,
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[5] Mason, F. Supersonic Aerodynamics. 2016, Supersonic Aerodynamics,
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[6]Cantwell,BJ.AircraftandRocketPropulsion.pp.1–21,AircraftandRocketPropulsion.
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[8] “Inlet Performance.” NASA, NASA, 5 May 2015, www.grc.nasa.gov/www/k‐
12/airplane/inleth.html.
[9]“Gas Turbine Theory”, H.I.H Saravanamuttoo, G.F.C Rogers &.H. Cohen, Prentice Hall, 5th
Edition 2001.
[10] “Aircraft Engine Design”, J.D. Mattingly, W.H. Heiser, & D.H. Daley, AIAA Education
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[11] “Elements of Propulsion – Gas Turbines and Rockets”, J.D. Mattingly, AIAA Education
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[12] “Jet Propulsion”, N. Cumpsty, Cambridge University Press, 2000. 5. “Gas Turbine
Performance”, P. Walsh & P. Fletcher, Blackwell/ASME Press, 2nd Edition, 2004.
[13] “Fundamentals of Jet Propulsion with Applications”, Ronald D. Flack, Cambridge University
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[14] “The Jet Engine”, Rolls-Royce plc. 2005.
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Addison-Wesley Publishing Company, Reading, Massachusetts, 1965.
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(2015). Aerodynamic Shape Optimization of a Dual-Stream Supersonic Plug Nozzle.
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[19] Chutkey, Kiran & Vasudevan, B & Balakrishnan, N. (2014). Analysis of Annular Plug Nozzle
Flowfield. “Journal of Spacecraft and Rocket.” 51. 10.2514/1.A32617.
[20] Debiasi, Marco, and Dimitri Papamoschou. Cycle Analysis for Quieter Supersonic Turbofan
Engines. “37th Joint Propulsion Conference and Exhibit”. 2001, doi:10.2514/6.2001-3749.
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[22] Amoo, Leye M. On the Design and Structural Analysis of Jet Engine Fan Blade Structures.
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[25] Samuelsen, Scott. Rich Burn, Quick-Mix, Lean Burn (RQL) Combustor. University of
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‐87‐
Appendices
AppendixA:ComputationalFluidDynamicAnalysis
Figure54:(a)ridesideprofileofsimulatedpressureandmachspeeds(b)Shearstressand
pressureformation(c)Acousticpowerlevelreadingatcruiseconditions
‐88‐
AppendixB:InletDesignAnalysisTradeStudies
Figure55:TradeStudyandBaseline
InletDesignChoiceSelection
‐89‐
ChanelExtendedControlInlet‐Design1
(a)
(b)
(c)
Figure56:Design1sidecutplotprofileviewfor:(a)Pressure(b)Velocity(c)Acoustic
PowerLevel
‐90‐
SupersonicSpikeExtendedControlInlet‐Design2
(a)
(b)
(c)
Figure57:Design2sidecutplotprofileviewfor:(a)Pressure(b)Velocity(c)
Temperature
‐91‐
AppendixC:NozzleDesignAnalysis
(a) (b)
(c) (d)
Figure58:Design1sidecutplotprofileview:(a)Pressure,(b)MachNumber,(c)
Temperature,and(d)Velocity.
‐92‐
(a)( b)
(c) (d)
Figure59:Design2sidecutplotprofileview:(a)Pressure,(b)MachNumber,(c)
Temperature,and(d)Velocity.
‐93‐
AppendixD:CarpetPlots
TheplotsgeneratedinAppendixDprovideinformationontheperformanceofthe
baselineaswellasthedesignedengineatthedesignpoint.Inthiscase,thedesignpointof
theenginesisobservedatsupersoniccruise(Mach1.6).ThePARAprogramprovidedbythe
AIAAsoftwarepackagesuitefromtheElementsofPropulsionTextisused.Inputparameters
areplacedinsidetheprogramandtheoutputsforeachofthetradestudiesareprovidedin
the carpet plots. Each plot is with respect to Specific Thrust and TSFC. The carpet plot
features two varying inputs based on a maximum and input value for the number of
iterationsrequiredforthecalculation.
Toreadthecarpetplotstheformatisasfollows:
#Cycle‐VarM0/Tt4/Pic/BPR/Alt
‐94‐
TradeStudy1:T4vsFPR
TemperatureatT4 FanPressureRatio
Minimum:2600R Minimum:8
Maximum:3200R Maximum:16
‐95‐
TradeStudy2:FPRvsCPR
FanPressureRatio CompressorPressureRatio
Minimum:8 16
Maximum:16 32
‐96‐
TradeStudy3:T4vsCPR
TemperatureatTurbineInlet CompressorPressureRatio
Minimum:2600R 16
Maximum:3200R 32
‐97‐
AppendixE:AircraftDesignComputerAidModels
Figure60:Design1conceptwithstraightdeltawinggeometry(isometric,front,rightside
respectivelyprofiles)
‐98‐
Figure61:Design2conceptwithdoubledeltastraightwinggeometry(isometric,front,
rightsiderespectivelyprofiles)
‐99‐
Figure62:Design3conceptwitharceddeltastraightwinggeometry(isometric,front,
rightsiderespectivelyprofiles)
‐100‐
Figure63:Frontalnoseaircraftdesignbaseline:(isometric,rightside,frontrespectively
profiles)
Figure64:Frontalnoseaircraftdesignextendednoseoptimization:(isometric,rightside,
frontrespectivelyprofiles)
‐101‐
AppendixF:EngineInitialConcepts
Figure65:EngineConcept
ShowninFigure65,theengineconceptdepictsadualspoolmixedflowturbofan.The
enginewillbetestedwithvaryingnumberofstagesforthecompressorandtheturbineto
‐102‐
determinethebestcombinationforoptimalperformance.Theenginewillbeoutfittedwith
acustominletandnozzletoexceeddesignrequirements.
Figure66:ConceptNozzleGeometries
Figures 66 depicts different convergent‐divergent nozzles to achieve supersonic
thrust.Thetwonozzlesexploredarethebellshapedandconeshapedones.Furtherteststo
seewhichnozzlefitstherequirementswillbeconductedafterthepressurevaluesarefound
attheendoftheengine’sturbinestage.Eachnozzlewillhaveadifferentrateofpressure
expansionwhichwillresultindifferentmaximumpressurevaluesatthenozzleexit.
‐103‐
AppendixG:FinalEngineDesignPowerplant
Figure67:Engineisometricandsideprofileofinternalviewingofsupersonicgeometry
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AppendixH:HistoricalDataPlots
Figure68:SpecificFuelConsumptionvsoverallefficiencyforcommercial/civilaircraft
Figure69:BypassRatiovsOverallEfficiencyforcommercial/civilaircraft
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Figure70:OverallPressureRatiovsOverallEfficiencyforcommercial/civilaircraft
Figure71:Specificfuelconsumptionvsthrustforcommercial/civilaircraft
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Figure72:Graphofoverallefficiencyversusbypassratioformilitaryaircraft.
Figure73:SpecificfuelconsumptionvsOverallefficiencyformilitaryvehicles.
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Figure74:Overallpressureratiovsoverallefficiencyformilitary/civilaircraft
Figure75:Specificfuelconsumptionvsthrustformilitary/civilaircraft
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Figure76:OverallPressureRatiovsThrustforMilitaryAircraft
Figure77:BypassRatiovsThrustforMilitaryAircraft.
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Figure78:WeightvsThrustforMilitaryAircraft
Figure79:InletTemperaturevsThrustforMilitaryAircraft
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Figure80:TSFCvsThrustforMilitaryAircraft
Figure81:BypassRatiovsTSFCandFanPressureRatioforMilitaryAircraft
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Figure82:InletTemperaturevsOverallPressureRatioandTSFCforMilitaryAircraft
Figure83:InletTemperaturevsBypassRatioandTSFCforMilitaryAircraft
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Figure84:InletTemperaturevsOverallPressureRatioandEngineWeightforMilitary
Aircraft
Figure85:InletTemperaturevsBypassRatioandEngineWeightforMilitaryAircraft
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Figure86:OverallPressureRatiovsThrustforCommercialAircraft
Figure87:BypassRatiovsThrustforCommercialAircraft
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Figure88:WeightvsThrustforCommercialAircraft
Figure89:TSFCvsThrustforCommercialAircraft
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Figure90:FanPressureRatiovsBypassRatioforCommercialAircraft
Figure91:FanPressureRatiovsBPRvsSFCforSupersonicMilitaryAircrafts
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Figure92:FanPressureRatiovsOPRvsSFCforSupersonicMilitaryAircrafts
Figure93:FanPressureRatiovsBPRvsEngineWeightforSupersonicMilitaryAircrafts
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Figure94:FanPressureRatiovsOPRvsEngineWeightforSupersonicMilitaryAircrafts
Figure95:FanPressureRatiovsBPRvsEngineWeightforCommercialAircrafts
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Figure96:FanPressureRatiovsOPRvsSFCforCommercialAircrafts
Figure97:FanPressureRatiovsBPRvsEngineWeightforCommercialAircrafts
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Figure98:FanPressureRatiovsOPRvsEngineWeightforCommercialAircrafts
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AppendixI:ParametricCycleAnalysis
Table7:ParametricCycleAnalysisExcelSheet
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Table8:Tableofconstantvaluesforparametriccycleanalysis
Table9:Detailedcalculationsinvolvingpropulsiveandthermalefficiency
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Figure99:ParametricCycleAnalysisProgramforCandidateEngine(Trial1)
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AppendixJ:TOPSISAnalysisandDesignMatrix
Figure100:Designmatrixforpreliminaryselection
Figure101:PrioritizationMatrixforTOPSIS
Figure102:QualitativeScaleandFinalRankingforTOPSIS
Figure103:FinalizedTOPSISDataMatrix
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Figure104:Normalized,criteria,weighteddata,idealsolution,distancefromthepositive,
andnegativematricesforTOPSIS
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AppendixK:InitialWeightCalculations
Figure105:SizingCalculation
Figure106:InputsfortheBeguetRangeequation
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Figure107:BreguetRangeEquationcalculation
AppendixL:TURBNTurbineAnalysisProgram
Figure108:TURBNStage2Analysis
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Figure109:TURBNStage3Analysis
Figure110:TURBNStage4Analysis
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Figure111:TURBNStage5Analysis
Figure112:TURBNStage6Analysis
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AppendixM:Reflections
Challengeshavebeen faced from the beginning of the project. Initially, to gain an
understanding on what direction the group was to take, research was explored on any
currentsupersonictransportaircraft.Laterresearchwasconductedonthoseincorporating
the use of turbofan engines. Both situations were initially retarded by lack of public
information and a seemingly never‐ending encounter with proprietary information.
Eventually,throughpersistentandcollaborativeresearch,enoughdatawasfoundtocreate
astartingdesignpoint.Afteradesignpointandcorrelatingenginechoiceswerefound,the
focusshiftedtowardsgatheringhistoricaldata.Thisagainbecamechallengingduetolimited
informationandhaltsinretrievingoutsidesources(e.g.Jane’sAeroEngines).However,the
team was able to find a list of hundreds of engines to use for trade studies. This was
completedsimultaneouswithindividualresearchanddatacollectionfromvarioussources.
Once enough historical datawas found, the parametric cycle analysis began. This
processprovedmorechallengingthemoreitwasworkedon.Havingtoanalyzethemany
parameters, equations, and variables that go into PCA was challenging. After all of the
constants,assumptions,andstandardvalueswerecollectedanddocumentedonanExcel
sheet, the necessary thought process began to unravel. This was aided by the use of
aerospacetextbooksandwebsitestohelpbreakdownthemanyequationsandvariables.
Eventually, enough researchwasdone and the equationswere translatedonto theExcel
document;however,thevaluesthatthenumericalanalysisyieldeddidnotmakesensebased
onthereferencesused.Tocheckiftheproblemcamefromtheformulas,handcalculations
weredone.Theproblemwasnotwiththeequations,butitwaslaterfoundthattheunits
usedinsomeofthevariableshadtobeconvertedtomatchtherestofthedocument.After
severaliterations,theteamwasabletosuccessfullygenerateaPCAforthebaselineengine
with the intentions of running the program again with the values from the different
computationalmethods.
ProceedingthePCAwasthegenerationofachartthatdisplayedthethrustandTSFC
(thrust specific fuel consumption) design margins. To do this, the total drag had to be
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calculated.Thishadtobestrategicallytackledbyseparatingthecalculationsforthewave
dragfromtheotherdragforcestheaircraftandenginewillface.Usingdesignparameters
fromNASA/CR‐2010‐216842,theExceldocumentscreatedfortheproject,andthebaseline
model describedbyAIAA, the totalwavedragwas calculated onExcel and thenused to
determinewhichpowerplanttheteamwouldchoose.Thisthrustvaluewillhelpshowwhere
thedesignfallsinrespecttoathrustversusTSFCgraphandifthedesigncriteriaweremet.
Creating the design curve has been halted due to insufficient information on the actual
design.Thiswillbelatercorrectedafterenoughsimulationsandcalculationsareperformed.
Anotherchallengecomesthroughattemptingtocreatebudgetfortheproject.Most
oftheprojectwillbedonethroughcomputersoftwarethatisfreeorhasaminimalcost.The
team did set up a prescribed budget to complete the project covering any fees deemed
necessaryforcompletion.Concerningatheoreticalbudgetformanufacturingthedesign,this
hasproveddifficultsinceamarketforsupersonictransportvehiclesdonotexistoutsideof
themilitary(whomdonottendtohavebudgets).Furtherresearchintothiswillbedonein
futurework.
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AppendixO:Contributions
A‐Alain J‐Jordan C‐Chris
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A‐Alain,J‐Jordan,C‐Chris