undergraduate laboratories in aerospace engineering · pdf file– ae 460: aerodynamics...
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Undergraduate Laboratories in AerospaceEngineering for Discovery, Diagnostics, and Theory
Greg ElliottDepartment of Aerospace Engineering
2UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Outline
• Aerospace Engineering at UIUC• Laboratory Curriculum• Discovery Course Laboratories• Diagnostics, Theory and Design• Lessons Learned• Conclusions
3UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE Laboratory Curriculum
• Discovery Course: AE 100 (Freshman)Objective: Introduce students to aspects of aerospace engineering giving them hands-on problem solving design and data collection experience.
– Spacecraft and Rocket Section– Aircraft Design Section
• Upper Level AE Laboratory CoursesObjective: Typical Junior/Senior lab to introduce students to experimental methodologies, techniques, diagnostics, and confirmation of theories taught as part of the AE undergraduate curriculum.
– AE 360: Structures & Controls Lab– AE 460: Aerodynamics & Propulsion Lab
4UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 100: Intro to Aerospace Engineering
• History of Aircraft Design • Case Study of Vehicle Development• Aircraft/Flight Theory and Design• Engineering Ethics• Hands-on Experiences
– Discovery Flights
– Radio Control Flying and Aircraft Performance– R/C Glider Design Project
Piper Archer III UIUC Institute of Aviation
5UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
R/C Flying and Aircraft Performance
• Student R/C Flying Experience (CCRCC-AMA)
• Instrumented R/C Aircraft Performance
Description: Students have the opportunity to pilot a 4-channel R/C trainer with hobbyists from the local R/C flying club. Students learn about basic flight maneuvers and aircraft control.
Description: Students collected data from instrumented R/C aircraft with on-board imaging data recording and telemetry for class examples and home-work problems.
6UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Instrumented R/C Aircraft Flight Testing
• Engine Temperature
• Current / Voltage
• Telemetry
• Servo Positions
• Angle of Attack
Eagle Tree Systems• GPS
• Altimeter
• Pitot/Static Pressure
• x / y Accelerometer
• Optical RPM GPS
DataRecorder
Telemetry
X / YAccelerometer
Angle ofAttack
Pitot/Static Probe
7UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Instrumented R/C Aircraft Flight Testing
R/C Aircraft – Eagle Tree Systems Airspeed and Rate of Climb
Lift, Drag and Control Surfaces
• Engine Temperature
• Current/Voltage
• Telemetry
• Servo Positions
• Angle of Attack
Eagle Tree Systems• GPS
• Altimeter
• Pitot/Static Pressure
• x / y Accelerometer
• Optical RPM
GPS
Pitot/Static Probe
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Angle of Attack [Deg]
Coe
ffici
ent o
f Lift
No FlapsFlaps Extended
Linear (No Flaps)
Linear (Flaps Extended)
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Alti
tude
[ft]
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Spee
d [m
ph]
Altitude [ft]Speed [mph]
Airspeed and Rate of Climb
8UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Instrumented R/C Aircraft Flight TestingStall and Flow Separation
Video Camera
Tufts
9UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
R/C Glider Design ProjectDescription: Students are given a foam wing, battery pack, and flexible servo package which they utilize to design and evaluate the performance of a hand-launched glider.
• Initial Measurements and Calculations– Wing, Battery, and Servo Package
Battery Package
Servo PackageWing
10UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
R/C Glider Design Project
• Conceptual Designs and Evaluation– Tail and boom configuration
Dual Tail Boom
Single Tail Boom
Tail Configuration
11UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
R/C Glider Design Project
• Design Calculations– Tail length– Tail and control surface sizing (TVR)– Moment, force, and stability calculations
– Component dimensions and lay-out• Construction
FwFh.tail Fv.tail Ftb FbpFsp
AerodynamicCenter of the Wing
Ffb
12UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
R/C Glider Design Project
• Performance
• Powered Flight
• Report
13UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Aerodynamics & Propulsion Lab
Description: Senior level course with in-class lectures and group laboratory exercises.
Topics cover basic concepts in aerodynamics and propulsion highlighting:
• Experimental methodologies• Diagnostics• Data analysis and presentation• Theoretical analysis• Reporting
14UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Laboratory Exercises
-1.0
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0.000 0.002 0.004 0.006 0.008 0.010 0.012Time (Seconds)
Am
plitu
de (V
olts
)
Raw Waveform1 Harmonic2 Harmonics5 Harmonics10 Harmonics
Airfoil Pressure Distribution Experiment
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Angle of Attack (degrees)
Lift
Coe
ffici
ent
LabView and Digital Data Collection,Control, and Analysis
Wind Tunnel Calibration, UncertaintyAnalysis and Pressure Measurement
Airfoil Lift and Surface Pressure Cylinder wake, drag, turbulence andhotwire anemometry
0
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-5 -4 -3 -2 -1 0 1 2 3 4 5(Y-Y0)/D
σ/U
inf
X = 38 mm Hot-wireX = 89 mm Hot-wireX = 146 mm Hot-wire
15UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography Objective: Students operate a subsonic and under-expanded supersonic jet over a range of conditions. Utilizing various methods and assumptions the thrust is calculated. Schlieren photography is used to characterize the flow field and shock/expansion waves.
• Experimental ArrangementSchlierenMirror
SchlierenLED
Balance
LoadCell
SchlierenOptics
Pressure/Controller
PressureRegulator
LoadCell
Jet
PitotProbe
StepperMotor
Acoustic Silencer
16UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Collection
17UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Analysis– Force & Moment Balance
18UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Analysis– Control Volume Analysis
[ ] ∫∫ +−=RR
atm drrrrvdrrPrPThrust0
222
02 2)()(2)( πρπ[ ] exitexitexitexitatmexit AVAPPThrust ρ2+−=
1. Bernoulli - constantdensity
2. Isentropic
3. Subsonic – Isentropicchoked flow
19UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Analysis– Velocity Profiles
Jet Velocity Profile
0
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-20 -15 -10 -5 0 5 10 15 20Radius [mm]
Velo
city
[m/s
]
Me = 0.36: Bern.Me = 0.36: Isen.Me = 0.59: Bern.Me = 0.59: Isen.Me = 0.77: Bern.Me = 0.77: Isen.Me = 1.0: Bern.Me = 1.0: Isen.Me = 1.2: Bern.Me = 1.2: Isen.Me = 1.4: Bern.Me = 1.4: Isen.
20UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Analysis– Thrust Calculations
Jet Thrust
0
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100 150 200 250 300 350
Stagnation Pressure [kPa]
Thru
st [N
]
Load CellBernoulli (Jet Exit)Isentropic (Jet Exit)Pitot Probe
21UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• Data Analysis– Schlieren Flow Visualizations
Subsonic Normal shockUnder-expanded
22UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Jet Thrust and Schlieren Photography
• On-Line Laboratory
23UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Golf Ball Design LabObjective: Using a 6” x 6” subsonic tunnel students design a “better golf ball” and measure the drag, velocity and turbulence profiles, and frequency spectra in the wake. Students design the experimental plan and compare measurements with a standard golf ball and smooth sphere.
• Experimental Arrangement
24UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Golf Ball Design LabObjective: Using a 6in x 6in subsonic tunnel students design a “better golf ball” and measure the drag, velocity and turbulence profiles, and frequency spectra in the wake. Students design the experimental plan and compare measurements with a standard golf ball and smooth sphere.
• Experimental Arrangement
Pitot/Static Probe
Hot FilmAnemometer
Traverse
25UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Golf Ball Design Lab
• Experimental Arrangement
Calibration Program
Data Collection Program
26UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Golf Ball Design Lab
• Design lower drag sphere– Modify sphere to have lower grad without
changing volume by more than 10%
27UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Golf Ball Design Lab Data Collection
Direct Force Measurement
FD = (FLC – Fs) (LLC)/LS
FLC = Force of load cell (Lbf)Fs = Load cell reading with
sting only (Lbf)0
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0 20000 40000 60000 80000 100000 120000Reynolds Number
CD
Smooth SphereGolf BallModified Sphere
Schlichting, Ref. 1
LLC Ls
28UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Mean Velocity Measurements Turbulence Profiles
Momentum Deficit Smooth Sphere Frequency Spectra
AE 460: Golf Ball Design Lab Data Analysis
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(Y-Yo)/D
σu(
y)/U∞
SmoothGolf BallModifiedSmooth AvgGolf Ball AvgModified Avg
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u(y)
/U∞
SmoothGolf BallModifiedSmooth AvgGolf Ball AvgModified Avg
7.60.430.4678500
7.10.390.4228200
% Difference
CD(Mom.Deficit)
CD(Load Cell)
Reynolds No.
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0 100 200 300 400 500F r e q u e n c y [ H z ]
Sphere
Golf Ball
Modif iedSphere
29UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Delta Wing
Laser Sheet Lighting Flow Visualization
Oil Surface Flow Visualization
30UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Pressure Sensitive Paint (ISSI)
Innovative Scientific Solutions Inc.
LEDLamp
4-Jet
FilterWheel
Disk withPSP
12-BitCCD Camera
31UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Pressure Sensitive Paint (ISSI)1.10
0.95
1.0
1.05
32UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
Red and Green (delayed)Illumination Beam
SeededFlow
Color digitalCamera
33UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
Initial Image Delayed Image
34UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
Color DigitalCamera
Microscope
Delay PulseGenerator
Syringe Pump
Micro-Channel
Two Color LED
35UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
36UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
X/H
Y/H
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1101009080706050403020100
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U [mm/s]U [mm/s]
37UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
AE 460: Diagnostics Demonstration Laboratories
Particle Image Velocimetry and Micro-flows
X/H
Y/H
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1101009080706050403020100
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38UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGNDEPARTMENT OF AEROSPACE ENGINEERING
Conclusions and Lessons Learned
• Laboratories at the freshman (discovery) and senior level were described
• Multiple set-ups• Corporate memory of laboratory development• Development of routines to regularly check
calibrations and operation of instrumentation• Demonstrate good and poor (planned) data as part
of the lab• Carefully consider how much information to give for
data analysis