3 UNCLASSIFIED

RELIABILITY-PREDICTION PROGRAM FOR ORGANICRANKINE-CYCLE ENGINE GENERATOR SYSTEMS

by

D.J. Hoffmann

November 1970

Prepared for

~ U.S. Army Mobijity EquipmentResearch and Development Center

under Contract DAAKO1-7 0.D-4142-0002

ARINC Research CorporationaSubsidiary of Aeronautica! Radio, Inc.

2551 Riva Road )PAnnapolis, Maryland 21401 f~'

NATIONAL TE.CHNICALINFORMATION SERVICE-

UNCLASSIFIED

UNCL:.SSIFIED

RELIABILITY-PREDICTION PROGRAM FOR (,RGANICRANKINE-(YCLE ENGINE GENERATOR SYSTEMS

by

D.A. Hoffmann

November 1970

Prepared for

UJS. Army Mobility EquipmentResearch and Development Center

under Contract DAAKOI-70-D-4142-0002

CAUTION

This report contains critical evaluations ofcontractor products, processes, or procedures.Distribution should be contrc lied accordingly.

ARINC Research Corporationa Subsidiary of Aeronautical Radio, Inc.

2551 Riva RoadAnnapolis, Maryland 21401Publication B02-01-1-1081

UNCLASSIFIED

ABSTRA2TF

A reliability-prediction program was conducted by ARINC Researeh Corporation toprovide th. U.S. Army tlobility Equipment Re?.earch and Development Center withquantitative reliability prediction.- of two manufacturers' organic Rankme-cyc!e enginegenerator systems and a computer program for calculating the predictions. Historical failuredata were compiled, and a reliability-prediction mathem:ical mo)dei was deve!oped. Acomputer program was developed, and reiiability predictions were made for the two systemsfor a variety of missions and environments.

Iii

I

FOREWORD

This report was prepared by ARINC Research Corporation for the U.S. Army MobilityEquipment Research and Development Center, Fort Belvoir, Virginia, under ContractDA AKO1-70-D-4142. Its purpose is to provide a quantitative reliability assessment of enginegenerator sy.tems currently being developed by Fairchild tiller, Stratos Division andThermo E!ectron Corporation.

SU(JMM AR Y

INTRODUcTION

This r np• sf. oresnt the reults of a reliabliity-prediction pr:.)gram for closed org••icRankine-cycle engmric- ,eeeratr sets. The prrmn was cnduc&l by ARINC ResearchComoration for the U.S. Army Mobility Et-prorent `,-rsewh e-)d Development Centw.during the perioNul~y 1970 to Sept.ember 19S0.

The Rankine-cycle generator systems ,d two i-ian!'ýacturrs - Fairchild liiiler, S.'ab.Division, and Thermo Electron Corporation - are ccnsidei•'• nr ibis report. Each i: aself-contained integrally started power-generat-or -ytem capable af fi,'-,t hours' operationon its own fuel supply.

RELIABILITY-PREDICTION MODEL

In preparation for developing the prediction model, parameters that, define the %'ysl:rnswere specified, together with the missions and environments. The reliability block diagraw sand prediction equations (mathematical model) were formulated from system fu-cPi::,schematics, drrawings, and diagrams.

FAILURE DATA

A number of failure-rate data sources were surveyed and the failure rates for similarcomponents listed. Operational factors required to adjust each failure rate to theenvironmental modes and manufactuers" estimates were derived. A Failure Mode andEffect Analysis (FMEA) was also performed.

COMPUTER PROGRAM

A computer program depicting the mathematical prediction mode! was prepazed. Thisprogram canr be exercised for any basic series-constructed system over a wide range of time.The output (reliability predictions) can be obtained for a variety of mission typet over fouroperating environments. The program was made sufficiently flexible to allow system-configuration changes, as well as failure-rate distrioutions other than the assumed constantfailure rate.

FLUIDIC-CONTROL APPLICATION

Tht- feasibility of utilizing fluidic control devices was investigated h:refly. Theadvantager and disadvantages of such devices, their estimated reliability, and areas ofapplic•t;on were evaluated.

vii

CONTENTS

Page

ABSTRACT . ..... .... ... ..... ... . .. ... . .. .. ... ... ... . i

FO REW O RD ............. ................ .. ......... . ... v

SUM M ARY ... .... ... .... ... ... . ......... . .. . ....... .... vii

CHAPTER ONE: iNTRODUCTION ................. ... 1

CHIAPTER TWO: B-ICKGROUND ....................... ...... 3

CHAPTER rHREE: RELIAB'L.ITY-PREDICTION MODEL . 5... 5

3.1 System Definitions ..... 5

3.1.1 Fairchild Hiller Stratus Division System ..............

3.1.2 Thermo Electro.,n Corporation System ......................

3.2 System Midssions ................ .............. 73.2 1 Mission Profile ...... .... .... ....... - .. 93.2.2 Environments ...................... 9

3.3 Failure Definitions ... .................... 103.4 Assum ption. . ................................... 03.5 Reliability Biock Diagrams ... ......... ................. 103.6 Reliabiity-Predi.tion Equation ....... ....... .... ....... 11

CHAPTER .iOUR: DAK A COLLECTION ................... ......... 17

4.1 Development of Equipment Failure Rates . .... ............ 174.2 Development of Equipment Maintenance Data ................... 20

CHAPTER FIVE: FAILURE MODE AND EFFECT ANALYSIS ............. 21

CHAPTER SIX: COMPUTER PROGRAM .............. 31

CHAPTER SEVEN: RELIABILITY AND AVAILABILITY PREDICTIONS ......... 33

7.1 Refiability Predictions .......... ................ ... 337.2 Availability Prediction ........ 31

Ix

CONTENTS (eont ued)

Page

CHAPTER EIGHT: FLUIDIC-CONTROL APPLICATION'..................... 35

CHAPTER NINE: CONCLUSIONS AND RECOMMENDATIONS. ............ 37

APPENDIX A: SOURCES OF FAILUIRE-RATE DATA ....... ........ A-

APPENDIX B: COMPUTER PROGRAM FLOWI CHART AND INSTRU.-'IONSFOR USE ............................................ B-i

ILLUSTRATIONS AND TABLES

Page

Figure 1. Rankine Cycle PV and TS Diagrams ..................... ...... 3Figure 2. Basic Flow Schematic for Organic Rankine-Cycle System ................ 4Figure 3. STRATOS Engine Generator Set .................. 6Figure 4. TECO Engine Generator Set ................................ 8Figure 5. Reliab~iity Block •)iagram, Organic Rankine-Cycle Engine Generator

System .......................... . 11Figure 6, Functional-Group Reliability Block Diagrams fcr STRATOS System ...... 12Figurrc 7. Functional-Group Reliability Block Diagrams for TECO System ........ , .14Figure B -1. Prediction-Program Flow Chart .......... B-2Figure B-2. Prediction Program ...................... B4

Tab'e I. Component Falure Data, STRATOS Engine Gene:rator Set . 18Tabl •.. Component Failure Data, TECO Engine Generator Set ............... 19Tab.e 3. Failure Mode and Effect Analysis ior S7RATO• Engine Generator S-_t ...... 23Table 4. Failure Mode and Effect Analysis for TECO Engine Generat.sr Set ......... 27Table 5. Rankinc-System Predicted Reliability , ...... . .... .. .... -, - 33Table 6, Estimated Steady-State Inherent Availability ....... 34

x

CHtAPTER ONE

INTRODUCTION

Under Contract DAAK01-70-D-4142 to the U.S. Army Mobility Equipment Command,ARINC Research Corporation assessed the relative effectiveness of two organic Raikine-cycle power plants under development for the Electrotechnology Laboratory at the U.S.Army Mobility Equipment Research and Devilopment Center (USAMERDC),

The purpose of the asses.ment was to make quantitative reliability predictions for thetwo candidate configurations and to provide USAMERDC with the basic tools forperforming future reliability analyses. A hypothetical system with idealized characteristicswas used to show the ultimate reliability of the Rankine-cycle power plant. The followingtasks were performed:

Review available information on the Rankine-cycle power plants and establishbaseline dataIdentify a representative mission and define system failure

Perform a Failure Mode and Effect Analysis

Develop a reliability-prediction model at the major-component level sufficientlyflexible to permit configuration changes and the use of various types of failuredistributions

Perform a reliability prediction of the two candidate systems and a hypotheticalsystem

Develop an estimate of the mean active-repair times for the candidate systems anddetermine the availability of the systems

This report preserts a backgrourd discussion and description of the candidate systems,Failure Mode and Effect Analyses for the systems, the prediction model and the predictionsthemselves, and a discussion of "be application of fluidic controls to the Rankine-cycleengine. The conclusions and recommendations resulting from the study are also presented.

CHAPTER TW'O

BACKGROUND

The U.S. Army is currently conducting a technical evaluation of silent ground-powersystems. The Rankine-cycle engine is one of the candidate prime movers for such a system.Two contracts to develop a Rankine-cycle engine generator set were awarded by the U.SArmy Mobility Equipment Research and Development Center (USAMERDC), Ft. Belvoir,Virginia, to Fairchild Hiller Stratos Division, Bay Shore, New York, and Thermo ElectronCorporation, Waltham, Massachusetts.

The closed Rankine cycle for steam. or organic w.rking fluids involves the fourtherniodynamic processes shown in the pressure-volume (PV) and temperature-entropy (TS)diagrams of Figure 1.

Ideally, the working fluid undergoes an isothermal and isentropic pressure increase inthe feed pump, process 1-2; and a temperature increase in the boiler at constant pressure,saturating, evaporating, and superheating the fluid, process 2-3., Process 1s-4 represents anisentropic pressure decrease in the engine; and process 4-1 is the constant-pressure heattransfer in the conder-ser, condensing the vapor back to a liquid to re-enter the feed pump.

P T

12 3 3

'' 4 I 2,4 4

V

Figure 1. RANKINE CYCLE PV AND TS DIAGRAMS

3 £8MG PAGE BLMIK

The organic Rankine-cycle systems have a potential problem area with the organicfluids. If overheated, the fluids undergo thermal decomposition, rendering the system use-less.

Figure 2 is a flow schematic for a basic Rankine-cycle engine generator set that uses anorganic fluid as the working substance. The numbers correspond to the processes in thecycle. The regenerator is used to increase the efficiency of an organic Rankine cycle. Theenergy of the -aperheated exhaust vapor is transferred internally in the cycle to the workingfluid after the fluid leaves the feed pump; this significantly reduces the energy required tovaporize or superheat the fluid in the boiler.

tsoiier Regenerator Feed Expander/ LoadLiquid Side Pump

40

Regneator Sde

Fuel in VprSd

Figure 2. BASIC FLOW SCHEMATIC FOR ORGANiCRAINKINE-CYCLE SYSTEM

CHAPTER THREE

RELIABILITY-PREDICTION MODEL

The term "reliability-prediction model" describes the block diagrams and equations thatdepict and mathematically relate component reliabilities to overall system reliebility. Thedevelopment of a reliability-prediction model encompasses several tasks:

Definition of the system mission

Definition of system failure

Statement of assumptiors

Development of reliability block diagrams

Development of reliability-prediction equations

3.1 SYSTEM DEFINITIONS

The two manufacturers' systems are similar. The major difference that might affectrehability is in the power output level of the generator sets, which affects, set size. Thefollowing systen, descriptions show the deieerences between the manufacturers' designs.

3.1.1 Fairchild Hiller, Stratos Division System

Fairchild Hiller Stratos Division, herinafter called STRATGS, is designing a 1.5-kWorganic Rankine-cycle engine generator set rated at 28 Vdc. Th: set will be inaudible at 100meters, will weigh approxnimately 150 pounds, and will measure approximately 2' X 2' x 2'.

Figure 3 is a flow schematic of the STRATOS generator set. The organic working fluidis FC75. To protect against overheating or overpressurization, a thermal sensor is placed atthe fluid exit poiat on tne boiler to shut the system down. A pressure-burst dise is alsoplaced in ths flaid loop for additional protection of the system components in case thethernal s,-nsor fails and the system becomes overpressurized to the point of catastrophicline or component ruptur,..

The turbo alternator pump is the unique component in the STRATOS generator set. Itcombines three components into one on a single rotating shaft. The two fluid-film journalbearings and a thru.t bearing are lubricated by the working fluid., The unit is hermeticallysealed in the fluid loop, two fluid drains in the alternator case remove entrapped FC75.UiquW FC75 flows in a coil around the alternator portion of the turbo alternator pump tocool the wirdings. The power-conditioning circuits are mounted on a cooling plate for thesame purpese. This keeps all of the major power-producing elements at a constanttemperatue during system operation.

PressureOvertemperature Burst Startup

Sensor Disc Vlo

ChenkrolnSensor

VuneaFelvev

UTeprature i

Segensatr

___ __ __ __ Condensera 7Valve 3 FTaTn EN IN GFE AlO SE

6l to

The condenser fan and the fuel pump are driven by variable-speed motors. The motorspeeds are adjusted by thermal sensing circuits to maintain constant fluid-loop conditions.

The alternator speed is kept constant by a solenoid modulation valve in the fluid loopjust prior to the turbine inlet. The valve is controlled by a circuit that detects the output ofthe alternator and sends a signal to the solenoid to vary the flow rate to the turbine. Thefeed pump is a centrifugal noncavitating pump whose output is kept constant by thealternator's fixed RPM.,

"1 ne fluid loop is hermetically sealed., It is therefore repairable only at the depot level.Most support components in the systeras (see Chapter Two) are repairable at theorganizational levei of maintenance. The electrical and electronic circuits are currentlyplanned to be field- or depot-repairable.

3.1.2 Thermo Electron Corporation Syste.a

Thermo Electron Corporation, hereinafter called TECO, is designing a 3-kW, 120-VacRankine-cycle generator set. It will be inaudible at 100 meters. weigh approximately 300pounds, and measure approximately 2.5^ X 2.5' X 2.5'. Figure 4 is a functional schematic ofthe TECO generator set.

CP34, an organic substance, is used as the working fluid. To protect against overpressureor temperature, safety sensors are placed in the fluid loop. The boiler requires a buffer fluidaround the organic fluid because of the extreme temperatures. The buffer fluid transfers thethermal energy to the working fluid. The flow energy of the vapor is converted to rotarymotion in a reciprocating two-cylinder engine that is coupled to the alternator. The vapor isthen exhausted through the regenerator to the condenser. A positive-displacement pistonfeed pump is gear-driven off the engine; it is located upside-down to form the bottom of theengine crankcase. The crankcase is filled with a silicone lubricant to !ubricate both theengine and the feed pump. The silicone is miscible with the CP34; a fluid/lubricant separatoris thus necessary in the loop since the seals and rings in the engine and feed pump are not100-percent leakproof.

When the system is not in usw, the working fluid and lubricant characteristically migrateto the engine crankcase. A starting fluid reservoir is placed in the loop to drain theaccumulated fluid from the engine. This reservoir provides the fluid to the start pump,preventing pump cavitation at system startup.

A motor-driven throttle valve is used to maintain constant engine speed, Alternatoroutput is sensed by a speed-control circuit, and a control signal is sent to the valve's drivingmotor.

The fluNd loop is hermetically sealed, except for the shaft seal on the engine crankshaftwhich must penetrate the crankcase to connect to the alternator, making it extremelyimpractital for the user or field-sul-,)ort maintenance facilities to repair components in theloop. Most of thl- -lectrical and electronic components, fuel- and air-supply components,and condenser fan are planned to be field-repairable.

3.2 SYSTEM MISSIONS

The U.S. Army Mobility Equipment Research and Development Center h-- establisheda goal of a 95-percent reliability for the generator sets. with a confidence level of 90

.7

w .

0

0E >

percent, for a mission duration of 24 hours and an inherent availability of 98 percent.ARINC Research Corporation used this requirement as a basis for developing tworepresentative missions.

3.2.1 Mission Profile

3.2.1.1 Mission I

The first mission is for the Ranxine-cycle generator set to start up in three minutes(0.05 hour) and continuously deliver power for 24 hours without shutting down. It isconr9ided to an external fuel tank, but this fuel source is not considered in the reliabilitymodel.

3.2.!.2 Mission !1

The second mission involves cycling the generator set through startup and powerdelivery four times in 100 hours. Two of the startups are hard starts, requiring six minutes(0.1 hour) each; tlhe other two starts require the normal three minutes. The sets deliverp wer continuously for 25 hours after each start.

3.2.2 Environmeazts

At the beginning of the project it was planned to incorporate the effects of temperatureand weather conditions as the environmental effects on the system. it became apparent,however, that there was little operational information on mechanical and electromechanicalequipment that reflected these environmental factors. Data were available on severaloperating applications for these equipments; the three of these which were used aredescribed below.

3.2.2.1 Portable Ground Environment

The generator set is in a portable condition, not rigidly mounted in a fixed, installation;it can be moved from place to place in vehicles traveling cver unimproved roads and can beloaded and unloaded manually.

3.2.2.2 Tracked-Vehicle Environment

The generator set is mounted on a tracked vehicle capable of traveling over open terrain..The set is subject to severe shock and vibration in transport. The sets will normally beoperated while the vehicle is not moving, although operation is not restricted to times whenthe vehicle is stationary.

3.2.2.3 Laboratory Environment (Hypothetical System With Idealized Characteristics)

The laboratory environment was used to meet. the contract requirement to develop aprediction for a hypotheticL system with idealized characteristics. The laboratoryconditions are based on the assumption that the sets are functioning in an ideal environmentwith skilled personnel performing the operational tests. It is believed that the data producedunder these conditions show the best achievable reliability for the prototype models andindicate what can be expected from production units in the field that are superior in designand reliability to the prototype generator sets.The system manufacturers currently believethat the best method to achieve higher system reliability is to improve the design rather thanincorporate redundancy.

9

3.3 FAILURE DEFINITIONS

The loss of any critical component that prevents the generator system from meeting100-percent power-o-atput capability results in system failure., A critical component is anyitem or part whose failure would preclude successful operation of the system or createsafety hazards. Included in this category are the components required for starting thesystem since without starting capability power output cannot be achieved.

Failure of any safety-shutdown circuit is a system failure. These circuits are fail-safe -that is, the loss of onie of them will automatically shut down the system.

3.4 ASSUMPTIONS

After the syst Ams, the missions, ai.d failure were defined, the following majorassumptions were male to establish prediction-model limitations.'

Once the system has exceeded the infant-mortality period, the failure rate does notchange during the life of the system (exponential distribution).

All components must function properly at the prescribed time in the mission forcomplete system success.

System safety-shutdown circuits are nat fail-safe.

Generator-set maintenance will not include any components in the fluid loop,because the loop is hermetically sealed by the manufacturer or depot.

3.5 RELIABILITY BLOCK DIAGRAMS

A reliability block diagram is a pictorial chart of a system or subsystem that depicts theinteractions between the components of the .,stcm and the effects of a component failureon the system.

Figure 5 iL the reliability block diagram for an organic Rankine-cycle engine generatorsystem composed of four functicnal groups or suibsystems.

Fluid-Loop Group - any component that comes into direct active contact with theorganic fluid

Power-Generation Group - the ccmponents and circuits that make up thepower-generation, -conditioning, and -rectifying segment of the generator sets(excluding the alternator in the STRATOS system, which is included in the fluid-loopgroup because it is hermetically sealed in the loop)

Electronic Control Circuits Group -- the circuits that contiol, regulate, and protectthe generator set, along with the electronic or electrical sensors providing the properinput signals

Support-Components Group - components or items that do not directly fall intothe other three groups and provide a supporting service to the end mission of thegeneratcr set

10

Power Electronic I SuppoitFluid Loop Generation Circuits Components

Figure 5 RELIABILITY BLOCK DIAGRAM, ORGANIC RANKINE-CYCLE ENGINE GENERATOR SYSTEM

Figures 6 and 7 are the functional-group reliability block diagrams for the STRATOSand TECO systems, respectively. A five-digit code is assigned to every block in the reliabilitydiagrams for identification in the computer mathematical model when failure distributionsare being inputted. Whenever a change is made in the diagram, it is necessary to add orsubtract a code depending on whether a component is added or removed.

3.6 RELIABILITY-PREDICTION EQUATION

The rehability-predictior equation expresses the mathematical relationships betweenthe system components in the reliability block diagram, showing how they are related tooverall system reliability.

The Rankine-system components have basically a direct series relationship. Thecomputer model calculates the reliabilities of all the component- individually. The failuredistribution of each component or circuit, the amount of accrued operating time on thecomponent, and whether or not the component is a redundant element in the overall modelare required for these calcilatiors. These data are inputted into the model with thecomponenrs five-digit identification number (see Chapter Six).

The series model for either generator system composed of n elements can be simplyexpressed as

nRs= I Ri(t) = R, - R, - R3 --"Rn

The equations for calculating the reliabihties from the four distributions used in this studyfor any single component are as follows:

Exponential

Ri(t) - e-Xit

Normal

f 1 2o2

t

11

BolrConnection, Air l. lM7Turbo-AltratorBoler and Fuel Control Start Vve Modulation ValvePump

Thermistor

1.1010 11020 11030 110'0 11050

Regenerator i ng Seetmn Condenser Condenser Fan Check Vidv',, Mam I11060 ~~Desuperheater 1 ntlThrst Il I C~t ntol T'hetmistor

11060 11070 11080 11090 1111

(heeI, Valve,. Pressure ICz)oliong Ccil,-Up L Regiilator Start-Up Pimp Turt Turbo,RJternato' P.m-:; Arerator Pump

11130 11140 11150 11160

[ oolinp Coil, Pipig.

Power Bellowis, Pressure R rressure"- P onde'e~mr Jlonts. Burst DLLC Refief Valve

(ondition'er Joints

1 1170 11180 11190 11210

(a) Fluid Loop. 11000

Voltage Voltag'e Voltage Poer FP-] uwerýRegulator Regulator Rp-ulator Cond:tLoning (.-,• t ,.flng

VRI VR2 VR3 Circui PS1 (Thi'tPS2 -]

14010 14020 14030 1 4 ,14 0 '10iJ

P7dtiomnwer Connector

t m uit PS3 2 Pi

11060 14070L j -

'b) Power Generation, 14000

FWuie 6 FUNCIrONAL-GROUP RELIABILITY B3OCK DIAGkAMSFOR STRATOS SYSTEM

St' tX riit Itge JlO-S'et' ,l~d I

:tci fiir Ov('rtemp-rature j Inle Timer Fu--Rt Control(.'ir,'il: t ('r'lt Circuit I'{Ir ot 'in Wit

16010 ol1•oo i60301o 14O0.016020 L--______

Slpeed.(',ontrol Specd-'Control Oversp-|e Control Ultasorc('Oruit Ot u It Circuit Connecting Atomizer Oicillator

Co('ndenser Fan Turbine Turbine Circuit Circuit

16066 16070 16080 15090 16110

[j lg vt~ 'ri Speed-Control SU itch, Temperature Senmir Temperature' SensorL Shutdown Control r & rU. I (oiitro,

[ •i '0 16130 16140 16150 16160

(c) Electronic Control CircuiL.-, 16000

FePupFuel Pump Ultrasoini Combustion F CombuqtionMotor Atomizer Air Fan Air Fan Motor

18010 18020 18030 18040 18050

Condian-r Cor, d.uer Fan4r-('ondene'r Fan Motor Ducting Battery

18oi6 18070 18080 18090 18110

and Fuel in.e t and Start Pump

Fittine, Fiter .hu;-off Valve otor I

8120 18130 8140 18150

(d) Support Compcpents. 18000

I"wurf- F crantinued)

SBoiler Fuel-Control Separator Throttle Valve Engine/Expander

Thermistor21010 21020 21030 21040 21050

1 Connection, rRegenerator Condenser Condenser-Fan Feed Pump By Pass Valve

Pressure Control21060 21070 21080 21090 21110

I~ Sarug-Fuui i Pessre-Piping and Press-jre BurstControl Starting Pump Burst Disc, JIint Drsc, 80rstReservoir 100 psi Joints Disc, 800 psi

21120 21130 2114G 21150 21170

F[ Fle,:iies

21]80

(a) Fluid Loop, 21000

F7Alternator, : Rectifier ____

Alternator Starting I and Batteryv I Connector, I- Winding • Charger 2 Pin

24010 24020 I 24030 I 24040

(b) Power Generation, 24000

F~gure 7. FUNCTIONAL-GROUP RELIABILITY BLOCK DIAGRAMSFOR TECO SYSTEM

If

(_ Burner (on:rol

I'lirt Ith-V a Ine Fuel-Rate Sleed-Sensing Con.denser Fani.09R Circuit Legit Circuit Logic Circuit Logic Circuit Log:c Circuit

L 10 26020 26030 26040 26050

F Co n tr ol Thermistor, Preseur,, Sensor,.

iertemperature Starting I Coirectsng Fuel Condenser FanCrutL~ogic Cnclutt - Circuits Conontro

26060 26070C I 26080 26090261

(c) Electronic Control Circuits, 26000

FuelPump FulPump Fuel-Line [ AtomizationLn1Foa Solenoid LFitrBurner Comrpressor

Rcservoir Fite and Motor

28010 28020 28030 28040 28050

Co.nbustion Air Combustion AirAtomizer Blowr Blower Motor Igniters Condenser Fan

28060 _ L_28070 28080 28090 28110

Condenser Fan Throttle-Valve Starting Pump Expansion Tank,Motor Dr•i ng Motor Motor Battery Boiler-Jacket

28120 28130 28140 28150 i 28160

%%j-r JaickettI-1 Il're-',Urc-9urert Fuel Lines and Fuel Tank andD1,- 2000 pIm Connections Shutoff Valve Duetng Pressure Switches

28170 I 28180 28190 28210 - i 28220J- _ i f fi

(d) Support Components, 28000

Figure 7 (continued)

Log Normal O)2

f 1 1 202

RI(t) f -a T e dtt

Probability

R. t) - Probability of succes

It was necessary to use exponential data for the predictions. However, during prototypetesting and development testing, with the proper data-collection techniques ,nd sufficienttest time, it will be possible to develop the true failure distributions for each component.

16

CHtAPTER FOUR

DATA COLLECTION

4.1 DEVELOPMENT OF EQUIPMENT FAILURE RATES

Since operationai data were not available for most of the components in the twosystems, it was necessary to research a number of failure-data sources to obtain data onsimilar components. The primary sources are Government and contractor data banks, whichoffer failure histories for a variety of mechanical, electrical, and electronic components. Thesources used for this study are listed in Appendix A.

To obtain appropriate component failure rates, all the available failure rates from thedata saurces used were listed and then screened for a best-fit average failure rate in a knownenvironmental cor.dition. The environmental conditions for the data ranged from thelaborat.ory to space vehicles. Tables 1 and 2 present component failure rates for the two-Rankine-cycle generator systems. It is emphasized that all of the failure rates areexponentially distributed,

It was asslmed that a portable generator set would not be subject to a singleer-ironment: therefore, three K factors were developed from the data sourcei. The fourth Kfactor is not environmentally oriented bni simply idasts the failure rate li.-ted in the tableto that developed b. the manufacture. it us thus possible to show the manufacturers'estimated reliability in comparison with the three environmental categories described inChapter Three. The K factors are as follows:

K, - Manufacturer Adjusting Factor

K2 - Portable-Ground-Environment Factor

K3 - T.ack-Vehicle-Mounted Factor

K4 - Laboratory (Hypothetical System) Factor

It is apparent from the tables that there are numerous adjusting K factors for eachenvironmental condition. The reason for this is that different data sources were us-'d andthere is no universai factor for all equipments. The failure rates of most equipments increaseas shock and vibration increase; thus a higher multirplying K factor is required for thetrrcked-vehicle environment to increase the average failure rate.

There are very few failurc data on mechanical equipments that show the effects ofextreme cold or heat on operating life. Temperature effects were therefore not considered inthe environmental conditions.

The delivery of the manufacturer's prototype system to USAMERDC for operationaltesting is the ideal time to begin a data-collection program. There is very lztfle operationalinformation on organic Rankine-cycle systems; to perform a complete evaluation of tie

17/

Th141e I C(All)NEN.T FAiLURE DATA,. TRAT0S ENGINF (.I'%RAW(R SET

I Wlork Componet Saw mili K1 K2 K3 K4

11010 lihal.r. 1501wkv4 5 3100 250 10 2

13020 Co.nmvtkmTeraorFelCnto 0 041 0 100 250 1

1103,1 341:"ali 6884 1M9 100 2590 ) ' 2

11040 M3odulation .tdvp385 00 I00 250 1 0 9

11050 Turbo A3ltmaorPumnp 242 2484 30 25 (12

31070 Mixng'ftw p up-du 426 3041300 250 1.0 2

31010h Coodenwt 53.1 357 300 250 10) 2

11090 Cunn-tnn. Ttmito.,Cndrnmr Pan (on1~,3 003 00 100 250 )0 2

11310 (Chik Valn.. 53wr 50 00 100 250 L.c 2

111201 Clm k Val-, Starup 50 00 10.0 250 10 2

11130 P..recfrr rgulat,.r 214 00 100 250 10 2

311110 .Stalt Pump 33 1 1325 10 25 02 1

11350 T 1a,.th~lo Altirnatw. vPump 4 21 003 00 30 25 02 2

31360 C-dmg Coil. Turtin Anirntot Pump 3 65 00 1.0 25 02 3

33170 Polau. P,'~ ( onditioning. 165 00 30 25 02 1

?113;,0 Luirnand Fittuilg 401 20 00 I00 250 10 2

311190 Pftr..Ru.-A D)nk 06 00 10 15 02 1

112W0 Pr-surý 3vlwf Va1e 1 77 00 10 25 U03 1

14030 %,'oILVi.g. ulsu. 1 32805 10 1-0 100 03 5

34020 VolItW Wr4vturat2 2914"714 30 20 10) too 3 5

, 40.10 Voltagi Rgu~atur 3 3507 1i'G 20 300 01 5

14040 mda1w1 114 0 2 0 3 .

I1405o 3n4;.,u' rCffma 2 02 10 210 100 01 5

14060 P.cw'odtu ,.ICnn, 3 0 075 10 20 100) 01 5

33W70 ICnn-t.-.. 2 Pin 1F-:akl 01 13G I1 5 0 03 1 I

1 6030 0-ih U .nojn w Cm-ult 20 10 10 601 025 4

IC-120 30- nt.-.1 Tiwcu.w-! 143 0175 30 775 0175

160,M) i-.i-n*m3~ur, Cinul 133 011 30v 775 014 1

160-10l N3 3snw i'mw cm- 500 0.1 30 50 03 4

3 6050 F~l 3Rtc ( nntMI Cift~l 1433 024 1 0 75 024 4

16060 sl4'.( ýn'r.Cdsrt. ( .n'1-f- Fail h3.3 0)23 10 715 024

160170 '.4

no3(m.d~1. Turll- 1453 024 10 75 1024 4

I3'.406I 3hf- Cm.l(.ue.Tr6$4 X43 3 023 19 715 024

160'X3) Cratir (.,. inn'3g f(rýu.3 25.0 09 1k 0o 667 025

If,1 I$, 3 nim-..nn- iz,IWCm nt M)00 03 30 5o3 03 4

1 h 12f1 lv-i-.In 4 on-t 250 0 352 10 667 0 B2 I

161310 I 314 .,t... 0.1'~ Lw-ro- 66 j 0 30) 15 0 213 4

16i 44) -. ,1n 31ti-rnpnt.tury Shutdo.~n 21a 24h4 13 25 01 1 3

f.;150 Fw-it-t-r f; 0i. (, . ?01. 1 30 2 ' 012 J

3638 Tzn3rr4ur Ion (o'n.ý 5* tv,1 9r 't1 Q 00 100 j250 1 0 3

,,.010 ro, I Pun.l. 494 1372 I10 25 I023 1

I ~ r KO:2 "W -1V 03 010 100 :n 20 2 3

114-03 %1-mt-r $133 25 30 1 17G 03 1

E'.5 .5,4.4.. %ýF, 02 i00 300 25(14 1 0 2

1mm 1,362 10 f60 0015 1

410~ 00 U 2

IAJ I P- lirne 124- 0 1 0 2. 075 I'S1'. islt' 1 41 ~00 10 2 5 021 3

1"120 L.,-, .Id rattinr Fun! 1 32 j00 100 5 0, 30 2

3143303 Fur; F.il, v 03 0)0 300 2z,3v 10 2

,11I u, wlOstfus 10 00 1 10 25 31 3

3451 rI'3gIj201 103 30 35

1) %T %)U RCIf ull fARtAM

%33 U!. -d3

Table 2 ('OWPONIENT FAILURE DATA. TECO ENGINE GENERATOR S'ET

Croutp failures Ila"Block Co•,mporiet Name, h p K2 K3 TourceNutmber million

21010 Bodef 49 1.02 80 220 10 3

210Y20 Cunnecton Tl.rmt-toor. Fu.l Control 003 J 00 10.0 250 1.0 2

21630 .vaurator 1.30 3.46 80 220 10 1

21040 Throttle Valve 213 165 1,0 20 083 1

21050 Egi0nr. Exitu;,-r 316 ! 0 475 1.0 2.24 0 275 1

21060 Rgegrirawor 420 1 059L 100 25.0 1.0 2

21070 (nwn-enr 533 13 M.e 250 10 1

21 ('onnection, Pr-esure Senir,. (ondenser Fan Control 0 02 00 100 2z 0 10 2

210 Ferd Pump 36,5 0.274 0 1.37 0.W434 1

21110 u rýun..Control Valve 5,92 204 80 220 1.0 3

21120 Starting-Fliud --r,.or p243 01975 10 2.A3 01 1

21130 Stan Pump 34 138 1.0 3S 0144 1

21140 p'.ure-BUMrg 1)nl. 100 Jim 06 0833 I0 15 0.2 1

2150 I.e wal F;ttng 40i 20 s0 100 250 1.0 2

23170 Prere-Burit Dak. SM0C 1- 06 0833 30 15 0.2 1

21380 Fkex h-r 3484 0287 t0 2'57 0,51 1

21 U-.-ti.r 07 286 80 22.0 10 3

2402i0 Altbrnato Star.terU waling 0.3 00 M 0 22ý0 10 3

230RU0 R-dtr.uua HAterM C(ltjWxr 20 ? 05 10 8C66 06 1

24040 (onnector, 2-pro f 4I.enale 04 00 100 250 10

10eControl Circuit 183.3 0356 10 7.5 0.2 426020 Bur.r Control and Ignitin Logw C'rc-wt jA 0.723 1.0 4.15 02

20030 'ueI-tate (*it 833 00 3.C0 7- 0.2 4

2"040 Sled44dontrol (',Crtt Altermnalor 833 00 10 7 5 02 4

26M0 Sperd-Contrl Circttit. Cnd.-n.'ar Pan 833 00 10 75 02 4

2060 hfle-r. e rShutudoa n Ciruit 143 0 I a 7.75 02 4

26070 Stating l.o9 Cmtvt 64.3 00 1 561 02 4

*NW Control ('onml4l.n ('utfct~ 25.0 00 1.0 t 6M (12 4

26091 Tcrmnistor, F•-l ( ontr', 06 00 3OG 254) 1.0 2

130 Prwxso.Se-nior. onent FanControl 35 00 s0 22 0 0 a

26031) kt. Punut,.I Ii!..3 Reser-ir 29)24 10676 10 25 02 1

2L4120 F o.-|'uenl , l'.*ler.ojcJ 53h 00 30 1 25 02 1J iI928030 FP-u.'3ine Fitehr 03 00 100 1 25 0 10 2

:3040 Buw-t 44 10 to 25 10 5

234054) Atowu,,atun CI.n, 4 wo,,r and IMo 2 44 13 1 0 1 - 0

" I!M,;0 Atoni.. I o01 00 1 O 10 I28A70 (,imnnic'u .AV, Blice,- 33 093 1 0 2 f 1

2 *d.p4o M,-tr. (ornnt-titAn BA.lr tom 235 0 0 :15 0 1- iziuwr, 1 0'.' ')0 10) 25 03 1

2.11 I ( Vmln.-r Fan C0 f 5 310 25 511 3

23 1334 \Inotr. ondtuc-nr t an 421 00 10 25 03 1

2,1-10 M5oto, rrIrxo0, %A, t. Dnming 1 51 00 100 25 343 0 2py1 M

53\--4r ictartn'tIPMp 0202 00 0 15 405

343'o 1 012. 1 C, I 25 02 1

2'tg, LspaI.,M Tank a. " . to 008 14 00 300 20 102xI41744 I-r-,.Itcr-Mt Iitk 2000 1-() 03 10 1 1 02G

h t caO J jnl l.nd --'n tý,n. 12 12 ()0 100 1 25 ( 3 0

P-i ___ __ I '%1 0,12 to 23 0"D--31 ). -. ri 12460 .04 30 '1 075 13SPre-cire iwtof It 7 M-' 0 172 1 U 2.5 0 1

) IT I %fit III f" $Ps F Ik1•|).

_______ Ii tn !. 217 \

3. . . . .. . . . . . . . . ..3. . . . . . . . . . .

generator sets, more accurate values of mean time between failures than provided in thisreport should be obtained. It will be necessary to develop a data-collection and feedbacksystem that will provide the proper historical information for improving design, lowering thecost of equipment repair, and reducing equipment downtime due to frequent failures.

4.2 DEVELOPMENT OF EQUIPMENT MAINTENANCE DATA

The information available for estimating component repair times is inadequate. Bothmanufacturers are planning systems with hermetically sealed organic-fluid loops; this willrequire that the generator set be transported back to a depot maintenance facility or themanufacturer for repair of any component that involves breaking this seal. The long-rangedevelopment plans include making the systems repairable at the field maintenance facilitiesby providing the necessary loop-purging and fluid-charging equipment at that level.

The only equipments intended to be repairable by the user or support-level maintenanceare system-support components and some of the power-generator components. The detaileddesign informnation concerning these areas is still being formulated by the manufacturers andis not yet adequate for developing realistic mean-time-to-repair (MTTR) values. However,STRATOS furnished a list of estimated repair times for the support components. TheMTTR for organizational maintenance is 0.7 hour.

A detailed examination of system repairability should be made for each system,considering the present repair-level capabilities of both the prototyp models andanticipated production models. Repair times can be obtained at the same time prototypetesting is being performed, and recommended design improvements can be reflected in thosevalues.

With the proper data-collection and feedback program, the best reliability, maintaina-bility, and availability figures can be obtained for the prototype designs and reasonablyaccurate estimates made for final production models.

20

CHAPTER FIVE

FAILURE MODE AND EFFECT ANALYSIS

The Failure Mode and Effect Analysis (FMEA) is an integral part of the reliabilityprediction. It is a systematic examination of all components of the system to identify theirfunctions and how they can fail and to determine the effects of each component failure onthe overall system- in relation to mission performance and personnel safety.

The identification of problem areas can lead to design changes that improve reliabilityand maintainability or produce savings for the entire program. Based on FMEA resultsprogram management can adjust the test and evaluation programs to provide maximumassurance that the Probzbility of critical failures has been either eliminated or reduced to atolerable level.

In an FMEA, mathematical probabilities of occurrence are normally assigned to thevarious failure modes. For this report, the FMEA is presented primarily to permit a betterunderstanding of the Rankine-cycle systems and the interaction of the components. Noattempt is made to assign failure-mode probabilities, because of the lack of historical dataon equipment of this type. and only the more prominent failure modes are listed. Sincethere is no inherent redundancy in the system, most of the component failures have thesame ultimate effect on the system - loss of power output. Tables 3 and 4 are the FMEAsfor the organic Rankine-cycle engine generator sets of Fairchild Hiller Stratos Division andThermo Electron Corporation, respectively.

The following elements comprise the FMEA format used:"Group Code Number - the numbers assigned to each component or circuit in thereliability block diagrams in Section 3.3

Description of Component/Assembly - the nomenclature of the components orcircuits as specified by each manufacturerFunction - the general description of each FMEA component's functioning in thesystem

*Failure Mode - the type of failure judged to have a probability of occurring during amissionFailure Cause - the most probable causes of the failureFailure Effect - the effect of the failure on the system and the missionCriticality - the severity of each failure mode and its related failure effect on adiscrete phase of the mission:

-Critical (C) - a failure that prevents the component from completing a discrete.-hase of the mission or is judged hazardous to personnel

21

Major (M) - a failure that significantly degrades the performance of thecomponent or delays its function such that it may not complete a discrete phaseof the mission

Minor (m) - a failure that does not have a significant effect on the ability of thecomponent to complete the discrete phase of the mission, but should berepaired eventually

Action Taken/Avoidance Technique - the action to be taken by the user to returnthe set to operational condition; or the technique that can be used duringmanufacture to eliminate, or minimize the effect of, the failure mode or to make theset easier to repair in the field

22

Tabk 3. FAILRE MOIW AND EFFECr ANALYSIS( FOR MFAIDS ENIN GNERATOR SEr

Qop FunctionnaSEC.*e R. aodeoo Cara. Mfeet cramtoo at*-reTritt

FLUID LOOP-11OU

11010 Itouer 434oo-i the working Rutupewi working, mmelwetlg. fatigue. then- Workinig fulud detteioamet i1ic safety dus.0 antprlnow~ (PC 75) from A, Midttb mat apainian from wrthwaunog. rauuuog troe damage from ."rhea,*4 b) tlittingtiqidl to 8 mpor. con- toulon in systm coniponents system down.

tua nd uffi th Imaar orkig fuid.cauing C

Rtuptured botettrasing Itot start. fatlgwvt-thermai Systiema Athdown r, riahe f,eipimloo -nolse

-113-V s~t~art a Risrikfluid flw ln (t1) Faolttid -to d Cw O oulacrotiondq~agg tl Fturel s~ystem, mt- the s) dew at OtWt xp (21 VAlurr to open: fromt voaimntnationt of work. otar-ut, w~ll bedda~rd.

until tW pretcratb.d 431 Future to open or heM fluid: brtiken spdof. b-4- powube damage to tu:,ho--ap -Sp(W eour and iloem completil, lows. or plunder alternator pump

- te2) Failure 9aopen; 4Utem-I tnhat down by uafey men-.

tempkratre sensors

I- (31 Failure to open kute trn- mCkaer1: sys.#4nm uuipat re,

dofby &W ridrt..11040 --Alodulktl-ný Control the nlow rate Vidtuetof sulietocow- Vasc f-o ae orimned floom nabiliy t. regulate r ani md WiI7

vats, of ith workig vapor foA (tow rontamiciauan, or torrosimi Ion of output rrgiul-sto the turbine to man Vs uo seasyfolbin constant alterntortteoin loigemms

itihlnow rf vapor to turbine

flow, Twbo, C`UftWM1&Warotar 1W enin ilFailure oftubattu iotninownt from beariag or literwti-romloroofutput untld iC-altetrotor Itubiblul ill on 3igid' War vw.e tunam ng bration ),srmihubedown

Aump sh"f winhte Atternatur, or coatact with noxatoMTA P) 2 jbih p-ide pti- 121 FAiure of itetrutor- Open gtndpi. shorted- ind, Prknwaa; rdrdeamn or losa of C

- -moat. and acermor katman or ar,,- aug output power-strun Amon-PO~~*II~I I.&pwe bouts to operate

(" pim at&.kIn ceoij: kmos..f uero c

I~ ~~~~~~~r oooPii pump 'I-pm ifk~o ho~ouanoddown

Ctork-d. Irbroke. leaking votigu. 4h".. sibrato. Lowt of working flud, rousing it Clet, " utow-pasm shutdown

o Iiereurme aumpefidum or litoling tup~ure tuaPes orwture at flaw, or fattgte Detelortlu awrt qtysavawrnhy he working fluid before arrai' from 4ilhratioo short. thermal - suitsdown

it enter the hol&e bi Fiiaed-tae ropt-on 4-pwwiontramflerifg beat from the Itejul iftsl

St~ri~t~ ai. Cl~ogged flu. on het trpt buildp onf(Am froml Itedi-e eftrnui. ¼

KRit(), Mut&sing m. oatw that hal tparuni~ as ante hu L-roioi .on Lo ..otsorm fluid. cminigt CFtut Ilubricated the T % P In~g srtnin alund.rk taatotatd workinig fuD. or jssin tdowr.

tDe-Super brrivqsi with thetape reeled. etude thermal st*s kapruirt, a c or buildp of Mt Cbeater before it entem It onut low k prenuntran hearing luhe

dvi ;et rousin os ereheato of

1160t' Cntalror Con~ftethie workinog I,"ea. Ptmptd tube I aio-frotý ,liL.tbotn. I-tem aidasno Ijuatit ronlo and Uettin t.zFfiudi trma ipor to or flba at Add watw-iua5i of faberted

liqud b)l, mo og. ironing, and btorta-beaot Couggd onihno" tubes Contauoinatioo from Aoftung Loss Ip f tpt PS 1t-st.of .- Moc fluiidhd 2!ý

flawd dr ,)ontuxpiwatn beforeI act" buildp can take~plare

I j J (~witw of etoilroaar Ataiesphenlcpano.a isoilani. t ofvimpvt Ona PHt moddt pervwnia- tou of

~~~~RW -A.- mdetr~-tv~ fin are.

taO I mfeitt reuew watin Faslore to open troto spoor. balt ynotsrd in Open: isarnwitabu ewtMai IIOM.9qlpfo =fluiii flow at s~arl-s~p otiter,- ojresetig e baggdor rmosptwnea.

I j ~ ~ ~ ~~~trm uaeimr~ts~lgbl ts~il~ lt toO siatt --

drirtu-onio of oratin flotuf- Iertins~atkjg Iu

111-20 0-1 C 'hstVse. j revent norklnkfluid Filure -o open Broken spoonr banl fuamed in ilpeu: ssdem *-r4o be 1, cSian: up ne fow tbiouh Aiire opesin clogged; or started -N

the Bunr pump dutring ea -~,- - em"ed preorujbofhi In:sw Ao.og as~e operation from 4r"ittg a"P ito .t u-r -

.ai beser output and Par-)meursite .mtd.ro

311M0 1 Fr-si I tmtain a rootatita Fad-r. nto uloAt lhe Soesn putt. eO^ge.L marld low preutore. omen out T-A P Ma CI PuoaK- ge Cr btoer vr~tlatrrFttrjtalor. Ipen-uft flow of aorta. prruser emin beronvgs -, s-am ulAiid~sw aed bairas% del Cut sotds11,anng m g fulu lubnWir to vi erg f.o~lubvirfiqltriAmota the T-AýP be of heAirsrutam fluid

I I m~eto alteraor. poadileI .oeons dracgN

I, 41111110 Marig M.4aft . wtssetnitil Miud keueoum pump Wmnrinqor boauJs or pump Pia8bh mtrisInat slr i 'ttuiri horrsirbl,-

ad 1- P Ftrupa pw.eitos and flaw t. output Caparit) natirharing. or t11.01 b-at.

bit) aitiy sar te untn. j _ sit ef i astor- to Pump 'atotr fasne rm (m .-peo. tatto- insart

~ .-~ew Jor rert"iete lig failse-

i(.-trsiat t. tarc n ano.~tt Pumpd1101 r -d.,- lte with 31110)

flZOO

Table 3. lcmtolitiflttdl

Codeu NI ofCmrnpaerwl Followic Fuatire Faliur Crill. AMMot ToolualS Ammrnbly mode Colonel Etffot rally. ollr Tormwllqweli

11150 Dralrk T-A.P- eal flui thtLaa (ek auiCuala org fluid Alieesaar fills with Omied CIm z tAo vieflu dingtaeLoom s k oloOP dso"

11160 Coating Trn"eut enesrre beost Raptured or da d FaiUe., th"euw dimw viborl. Gradual lm. of working fluid. CCado. Alec.- frrm Low, ulteseeaa woekntlagwll tube abnslaeol. "r rootarnlotve etuin @ýeloosEAa s huemdt.muma to the ciek luids warklut fluid d101ol'

11170 caoling Triaoral rate.lhcal Raptured or deAud Fatigue. themal strew, atak. Grdam" lsof a worktng fluid. CCasO. Form (arn the pow erma worhlenu ndie ue rdmtbgtlk or eontinarnlaud losineg ewes"oa syater dhut.Comriloaer dstloee to the work. working fluid down

ig fluid

11020. heesmtuar" Conecte the compa, Leak. "sIue Fatigu due to temperfate.. Lowli of working nowl. rcall** rnC Beta. the fluid loops filed1.090. JWn~eabom Imna lthe flied 21arb. 161,80"a oreeduci output to st.4m duet. Land moidled. a bloodirn leak111110 Piping and VArallow (Or tbersoa down hod diaubl be perfornmed Lto

Jalats and naPumslast at the insuarloop Integrity.Bellows Take pipin

111190 poommur,r Sates deuce in fleid Fell Weonw rule pms, bleoufrmturAg &4erm Permnute. lnsow at geim C Peeomasrt-nrit diskos Wepeesetvoeret Desk loopthaturei.-~. wee fial afteeer sylo ts " owk be.

pw~eut na' esde sy Fads at rated preesumr System arpeuedttoo Los of system with no darnow C to owm fkWm cornfsoter owe pumessim if Airult falls. disk works sa do. Wg to eoompooesetiIn flild t it diommllrd.dskrtown 'lerolt slignd loop Systesu soley preame ukill-

Volead abtove rate pee- Manufuacturing deleiet Lam at systiom with poindbte C down Ln m ,stihcli~eated withofte serlow mosooraoest darnage got

11210 lo-er Fanterntion an- Val"e tulle to deer Seekaw sputg. bell Pointwed loue *syste at-utp LILLY mrnRelee Vale. paretle with the in odiier. opemong ogged; hew I.elrded.10It posinto

start-ap raine (110301 sO sIaM cratd porreu duergep to T-A-Pto mumo flud to art Val. talk, t. oliess ba fro oot Open. q-stm diat&-ow b)Ma the bellow i4th lo swH) mordsiwpralerd on

P-1~~~a -m o -I-

R e r ai"r p o e rto r n Ji ~ F a , e u l at e O u t ( ~ a d j a s i re n ts . r e gu la t o r O u t p u t . N w 1 g o u t o f p e ~ s 1v S IC I S a d o ai pta, p i ow n t - -n W t

It40lt1Vtd.d ýfttsti diode sbrd-su pujet jwill womrnrsn dowuuss mid

14020 ) 'sAtac = p:I - Fko ua u falsuri.mllt Actremorse output -1tagoo StftC See 14010

I Rerflatet 'sR3 5 m rue a faolurebm Wnthermal stir.. -my:e.ePtalkao tow r0f41I toter at 1W no;tpst 6-ok. s___ ter powe an epobw"t

"4030 v olts" ltherph. tea-was.- fteetefle. tell. 'Omoulespaet offovawot euator Renrtow to. to lo of. SI C be 40.

ULMesaerse osefa ISg outprut - etorek tiooations "hro povrner power Iifme~s e sertarfý petorariol tota~e

ac to pirate)at

1405tl rle-e (7.4-14r aq-er ftollrttn fad %ormuot rsrnpaeerut feller Lows at alt power. 6)ee An c S 41Coor~a powe output free - shaork. 'ihoornase. therma shutdown Se14(

Cireost 1`2 aw to 4, tar aprro Are

VmeI, Vuse and e

VR1

111160 sr" Creert Reteiltarladh %rwt rsssoest fasluts. cssode;,w faa musto k-.s Io C trs 11Gs&rmte . p-we to atIII, sbus. tlsernal s tp ssoa eeds

sedosw run loud 101ees VORsudwnAPj to11-c o perotarn to total diveldown

IU40t4 sert1r I ('Merrt LMSo to wpumta pe lrtersssrtioe an f moors. luobdet to esusnert loud ts. jesS MILL ompno erninari eas2a -' mm.,ato 'Ira mi beak I mowelmen. Reporabl eta

RLSCTRORIC CONTROL. CHICIJIThSBUS111

16010 ~~Protest rIsmtrof (T Fasla of raes. Fade,, at chwSesupewet Open 4.k-e ,nlmtr W C Prewetemts leap m) heCrobar -fettue opewm lrsa itak uvoibriounn. thee most erdd wmle donlo eor~a4Icuorses I ettg erscdmtsm saldewoudrnim e etrkwai-ti dmnge ceuld rifoult a. neldle

pomentfllr uewd Irurn aresessitag

Pals fcminit. Surne as dues. SeArid " if mrie east riet C '4.14010duorsedmiff hke.sAttifg easem

16M2 1 ,., Re B" oplrs~cif th l'asler of wuun Se.W sa bheer Sstermm NsIL cs strt5-e 14010T-1 r )1 lisrt stud pup

brale bi-,ef faa 4a-W

order t. pitm thehealer with flid and

purge st a feel saps

Table 3 (aamoruiaedi

(;,e Noo tu irau a iawre FadureN vl'l"e C nip A.tivit T*aFqCode %as. cwpw CopaoI 1 jg ej c- Cat.t caf~ m).AtAlcdiuimTf qw j

14,61 (Itmpen. -'Rut do.. 5"m Fal. ulgau Same as abs.. syc wil Aud t down C S.. 14010.Wd t- are tmt if workiog-fluu i temp?

1614o alor e t#&ed 7020'F by .W .. s. f.6 ktoo*rqtoibuttwig off too supply F ,od.toauo 1.o ot If ~ a"utm

csa be urouxu) 4h nagwd

apred airtl , 61f 901 4Aimedfuaa'tioc. fwrst

14.0to tAmatf Flk up theO, e Faowkr to ruottal U~l. afledslelýaoMprAat fAll. Fiaumlro tIt.~un *)a c Mdkadf repiptanoet of aod. wouldTimer Cm,,on tiae"e from the 30, ap yquaeae ime do. to lempertuirt. o$Nouate douratiote Aad atuk. )A'tem

tttdfto.id, the rqta aItrr faf.kcv F~a.ir to mvsýar storup mc Wi Saft m hrs.ioald be ku:ato to

lwkrAtr a holle ei. to -sv to o ) awmofi arbunIol

frooý nm loV00 proper quetic,of Nite.tad Athatdoitra (anW. Nti

266041 A& and -6o wOOr Ookltfingd Lot 06 sillual t)Op eoistrokuit no.11 but"*~ ah -s (Am, f vkt 1"S 14010., l1,ý rate t-tperr~andt il to VOrt16160 tflttolttte the m~~..'A L_ of rmtrof full P&.lwo of op. or more Full spit "05 bodie Itatfo m4-'

of Airw tdfaee I?. Kd muei rw mw""nt

hfsle, geisu kmd dhottfii. .o a

fuel pump to proud La of t,ntt"m. faul Ful doued IArm t uofo%.

Itst OOOwt1t "keed at ri to 'Ada

WItM~t S--Coel e~ .i,,Okafud fadwt, of eoi.0 Coitistaaialm Ad.06 tef laltttow 10.. of output NI ~t Se 141110

161,51 t'.A-eser eotdesAl I I.0W1 to. up-. *atwt. grouado P.6W. afos motor eam006 Crrt't.,t t~tpeort, witn lfttto t-ite tnpovtkr aes tetbo auer t

mga the IA vu..at "o.ea rr;.,

to eato tem d 4epto.& rmoe

16070 Sp~ ton;rot 14 ae. tiue prid of Podurem of i timit~thounLo..oda L- 4 a~output ttniabor M r Se 11010y~d tRoatefls w eanpw aitrot armat -.fat-o ,'f

aett ýd a trodl 1t the, onI t

-11hos. thoK*tOo rmoada 145.

16444 tt.~o"Nd %koI av-r douan Paatevi of %uSme sAllt f.e'odeot-h raaj carool dhrrevews"m matErrs ot. ha aatting o;-f fast ,itmtrol dftuit auei the ,_.rto doit not f._-. maje 4 &.aotwiou. to tafopora

Tutmi, pph' altould tut mm, 0Wt ".eiaef hrii HkMTott. time m.1spi, ure to.,the arrtad Alm uotd I the apr-atro wn tttIltt wtl tha

I. 1 fi C .2 . 1 1 0 1

..stta. ratdrooor the "ouoofCrtotsi. Jootad. wm. Anorod Clen to afe4010._t tP4taarotu -Nim# eran woud.ed from sthermal orotd-or~ ml"todtt to

I S~tJSI otlttu

0.P I t i trea Igtoftom Ira.. 9 jt'pe~t cmotr wvr~t S..m ý ng&mdkt ." 14010)Ato-aa,t !u 4nC or.*t toimAmlIf- dý -gsf% M-

'sairora arPalal -1Oflrott a wd

Put Im~atmotWI .. 1A-

wsto' took' to 9

1610atrnhrt ~ Rat 1 -4 161w, t waitntFtesl oft 1664 164, at*1 nAon 'at. 17,

f1

fk

Table S7. icoettlotsodl

efu' Z I ~wmL Ceraw" FANe Acimum TAImw

of~~M" Compeeot Feeti

15111 Awl PINp Proeld tow pu~ore Futwu to supply fim L.Je 'aus Iftecomsmai-. r ysim htdoamwn IC Feet-fliefiter shou he btoeospstdaed aed MIAte quantity of Wee to mudow. beobaus Wele tm in lto System

1q20the ltcaOml sos. hem vbnmie. fogtfe I INOWi wiadhe shouted Fod pump an ml c *met shub e do.-uuSIKaed pe. "W siged Wo "apie r upasetby

Itedoctlou to belupt UK e ceeloslellic. Low. of M stegotol of Vol~g If

pee houe wom Will

18030 Lltcouee Atorml the fee inob Atomizer deuudo Diret Isow fehupeopus boomin of hdin to UC Fedl MWee shol he aMle to "AstmAtomlim the bole for proper. bmells. deterioration to im to mmcvrdet Im m bet.

elltzlest combudion of coshegtiome oyssAtom~m., follote Cell shoute. greemkd Fuel not stashed ot he Mec. IC Atossoork to Iuripeshke

or M opecomg itfuy bWand owl

IOCI0 C-ouebu~tM Supply the combo- Moetor fellowe Worm out hush.. .lod- Iedctlle. Of com1AIUMtle ale MIC Fmsan ml ooo shoul be dueledofd AVe Fan and dm a go the botin inshAouted ope. trm pammume. cedrgt 0 Wdodatis typic ee eplemmusst by esec.!Fu)0 M0 foeampietew me excoveasho iebst tospn&e In output to towa lom of WI*

tim a? the Wue tue WIN

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12) Fmn f "ieti () insmw$e

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9%heest; dmsg to mue

10110 Itatters. IP.-Mle 24 Vote wtatlu Low, of chume eeagek. to. of obectooyte Wmteoloatiou hat"es Cmw Wv ItC SYStem CEm he juempeetintd by S24 Volt. . nomles mod wiutm a rese boes hu. and to start volm if ard-l andmdae V ol smilla touch battery

m warm-up prie or she1f. ob tNo C e" go.laotiftu amor euNLda the putuetu

alt eummot he "lied

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(M vuhe I mat fee ISysd'" t *Am r pe w

F-W e me w-s r~ VlMtiou shock. fatage CI.sod stulos~tle ot eec usmft ep damaged lltec douo Mitruled coaced.t Imok. cam"u cOedatou is output

1"510 1 -It. km o system,

.18J50 s,-..etmd .5th 11140.-

Table 4 FAIMIA'k MGDC AND EPFFFT ANALYSIS IMR TFWG IN(;INE GENERATIOR iiIT

(%We Cam £ffrrý t cIy Aivihor. Thlvitq4

FLUID LOW-219le

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Code_ -c' ca Effuo reo Tdp

23320 sLwrtirt Fewed P~odde a newd ruesn. L~ostio. vopetwed ueoler FMb a fodurton .lkatb. sOwk 3wa of 5*0. ciold MICContalo for the sot pup "does *hAtbw

Ruro (211301 "Ae Wh foo Fls wak fol to op ls ~Uncloosko b~ eobM o. l vtsft losed.tm SYIWIIPs" p20M) to plY. Oin. f.. ,akko at dtpoeul new wM start

21130 Skimug nowd Nolde Is"t 11401 RP#octbo a pms noet Worn Motor brodw, POMPole othooy oa i

am4 to"~ ond prmesu and M1ew to put empodty lette bowetop or lnla 19/11*128140 &"WAo stut #A. Raklae qtde- bobg Loo of ft~ or owo si34

Fofeeee to pw.g Motor (Whee at. Fom ar. ýAtlwe go seen C*,..or powode - cleaR

pmp cale'.to& Rooemel (22110) asitoactlo foilore to flit C

21140 Premoer Borst Bfsfty don v IinMd Itod haIon ratd e M 0e M owtofatul dgwa Forwitue nog of 4).ea C Souuv44.M dIPIS jf

211110 tblOOl100. S OOD. Im end W.10 MWl 13.0 sieat "eiresla e

And 2M) Pat Inpe, etoa tou wn eyto t ongrsnwfeoeq.-I f.eletion a Fa"l at uated pe4.HY SyWM. ýJMi~ImtO U.'GN Lono syW.a ýA W C *A& somy p - etasory-p-o b"e *03w b*t lsa. *0k viorlia s,- doa t. o onepoes i. WAII ab* tei~d Wyk V~t

Fall skot M"te pet.- lWbotdaet defec own of a)4ete wstk p.clabd

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POWER CINIMATWOX - 240U

24010 1Al~to-ot. Gserrse the outWu llsiesloes"tio. los I.. SM Ceoeesto -laaeoe. Reue da.,p-o Mend Sterling pene of the systeir. of 2ý Output nottep- tvted rovdt3or to Ut. s)I*tU a"~

24020 AE pmd hIf Vow (.peo iebt ie AC di ems.L

2402 e~lefe sd Corf th hole, Foloe of beturlqsWN fieeromacicudOpoent hom p -r bl atec .b idt yse mb mea-e

ad" .*. aw oeto AP carging ro-.elt deto, a. lM~ore. Anoed. AMe syateg at Suabir led ontto a Searded 24--%i

atr""atica.f foreadov. cktkg Moot be bwepd by, ather Inlliy balueryfil m W e one o .ff * 0to ner i. w 114

set aug00e b,- ___e

ELECTRONIC CONTROL CImKUIT - 2000

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Los ofM~p"uar

du ty~o~ ovetiontdt,

i hUM01epompost distmrer 1&4&WMhY - keel of out*t N

I tuet jkrf fro-id, 3 sltno g-*-Atm Otp- control etarlt Sylwm sholdowora ulo- W* gWNt4..

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L- -". I! nopoviredo, or eh oubcoson oogsee 5tf Afel I-&t~ "to

O"Of tUeS, O.Fuort rcover

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oad It'Ca- ffel"wd opto- *0m In lok-"

pomp tono P I- cip or rempoatot *te )0. gtaat

i Law of control. foil -plow *It TAN d. -thefI oew Pvoapwv ý^ tv I

F.4 tt,

.0 f~tcw to ott

Table 4 Ieoatmued)

Jra Dounmpisia1 Faw Fuhrme Fadr. Actio TA.1'o co j lentrnt mole j causen Elffmnhi ArolIlhe Ti-thaw

ELECTRONIC CONTROLCIR.:CBLftS - 2SWC ftetmmd)

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spedFailwai deed krte of tn oo"emd) ýAattr Pf"FWZ dO tted ofrt- fWtw g

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uk.51~w dowit a" M..M si

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shutof Val* aMpi of liii e'apiwt ,*e dewjt8 esomako" fWi &eamd ~uau t bp hatL iak iwel b* wm-

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Ddm17 2)5 teku w40.4ortpw koLVWU ws ,11W.Ip~ mtoN* r

CHAPTER SIX

COMPUTER PROGRAM

The computer program was developed on a time-sharing system with basic FORTRAN•used as the language. This made the program suitable for use on USAMERDC's COMSHAREtime-sharing system with their preferred XTRAN language.

The program, described and illustrated in Appendix B, is designed to assess thereliability of a simple series system.. It can assess individual component redundancy whenthe appropriate inputs are provided for the redundant elements. Four reliability or failuredistributions can be manipulated in the program, the exponential, normal, lognormal, andprobability distributions. It is not necessary for all components to have the samedistribution, but one component cannot have two failure distributions at one time. The fourindividual K factors can be applied to the single component failure rate to account fordifferent system environments.

Appendix B also presents detailed instructions for exercising the program on atime-sharing computer terminal.

31

CHAPTER SEVEN

RELIABILITY AND AVAILABILITY PREDICTIONS

7.1 RELIABILITY PREDICTIONS

Reliability-prediction models were developed to represent the organic Rankine-cycleengine generator sets of Fairchild Hiller/Stratos Division and Ther-no Electron Corporation.From these models, a computer program was derived; it yielded quantitative reliabilitypredictions for the two systems.

Table 5 shows the specific results of the computer program for the two manufacturers'generator sets, operating for the two specified missions in the three environments.

Table 5. RA.NKINE-SYSTIEM PREDICTED RELIABILITY

K Mission i Mission 2Factor STRATOS TECO STRATOS TECO

Manufactur'er 0.9882 0.9941 0.9516 0.9757

Portable 0.9703 0.9766 0.8819 0.9061

Track Vehicle , 0.8752 I 08990 0.5736 0.6415

Laboratory 1 0.9950 0.9948 0.9794 0.9787

It can be seen that the more severe the environment, the lower the probability that thegenerator set will achieve the stated mission. The manufacturers' estimates for their ownsystem reliability are also included for comparison purposes. An examination of their dataand the final results indicates that they assumed a fixed ground installation rather than onein which the Rankine system would be portable.

There is little significant difference in the system predicted reliabilities for eithermanufacturer for dny given environment and mission. Operational analysis and accumulatedfailure data may y:,!d different empirical results.

33 G PAGE 1LAH4

7.2 AVAILABILITY PREDICTION

Tht- goal is to achieve a system inherent availability of 98 percent for each of theRankine-cycle generator sets. Inherent availability is based on active operating and repairtime and is the probability that the system will operate satisfactorily when called upon.

Mathematically, it can be defined as

MTBFAi = MTBF + MTTR

where

Al = Inherert availability

MTBF = Mean time between failures (hours)

MTTR = Mean time to repair (hours)

Since a large portion of the organic Rankine-cycle generator set will not be repairable at theorganizational level of maintenance, the estimate of the steady-state inherent availability iscalculated as follows:

MTBF (repairable components)A(t) = X Rt (nonrepairable components)

MTBF + MTTR (repairable components)

Table 6 shows the results of the availability predictions for the portable groundenvironment (K,) for the 24 hour mission only, The maintainability information needed toderive the inherent availability was not available at the time this report was prepared, exceptfor the STRATOS MTTR estimate o! 0.7 hour; the maximum specified downtime of threehours was therefore used to compare the impact of repair on both systems' availability,

Table 6. ESTIMATED STEADY-STATEINHERENT AVAILABILITY

L STRATOS TECO

Source MTTR A(t) MTTR At)(Hours) j (Hours)

Manufacturer 0.7 i 0.9171 -

Contract - j IGoal j 3.0 _ 0.9709 3.0 0.9783

Because of the large number of nonrepairable components and the high MTBF for therepairable components, the availability prediction diff, rs only slightly from the reliabilityprediction.

34

I

CHAFTER EIGHT

FLUIDIC-CONTROL APPLICATION

In the present concept the organic Rankine-cycle engine generator sets will becontrolled with electronic circuits. Since electronic circuits can fail catastrophically, anothermethod of system control is being investigated - the use of fluidic components that arepowered by the organic fluid's vapor pressure. TI. . investigation to date has considered onlythe electronic circuits proposed by the two manufacturers.

The critical question is whether fluidic circuits can completely take the place ofelectronic circuits in the generator set. It is possible, but it is also believed that completeflu.dic control is not practical. Fluidic circuits cannot compete with electronics in responsetime. Electronic responses are in microseconds and fluidics in milliseconds. Fluidic circuitsare also usually larger than their electronic counterparts.

Yet fluidics has some advantages over electronics in tha. the controls can behermetically sealed in the fluid loop. Contamination would be minimized, and there wouldbe no dust or atmospheric corrosion to affect relay contacts, open leads, or solder joints.There are few moving parts in a fluidic circuit, as there are in electronic relays or steppingswitches. Vibration is not a problem since the fluidic circuits are stacked and thenfusion-bonded, forming an extremely rugged device.

In the organic Rankine-cycle generator sets, the best areas for the fluidic circuits arethose in which pressure, temperature, or speed is being sensed and being converted tomotion to regulate flow. The circuits in the system that detect flu~d pressure and convert itto an output signal to control the condenser-motor, fuel-pump, and blower-motor -peeds arebest left as electronic circuits. These are electrical-signal input and output circuits;' presentfluidic circuits are not as compact, and their response time is slower.

The reliability of fluidic circuits is still in the very early prediction stage.. Very littleoperational information has been accumulated on the circuits because of their still-limiteduse. It is known that leaks and contamination, are the most prevalent failure modes, ane IL isbelieved that fusion-bonding the fluidic circuit and hermetically sealing the unit int• theRankine fluid loop would virtually eliminate these failure modes.

With the organic Rankine-cycle generator sets in the development stage, it may bepremature to consider fluidic circuits. Each engine manufacturer is still making designchanges, fiuid-loop conditions are being revised, and the exact method of system control isstill unknown in some instances. The design and fabrication of a fluidic circuit in itself is acomplex effort because of the many unknowns and the lack of off-the-shelf standaidizedcomponents

35

I

The feasibility of fluidic circuits should definitely be investigated and tentative designsestablished for the use of fluidic controls on the generator sets. The actual incorporation ofpartial fluidic controls should take place only when the organic Rankine-cycle generator setsfunction properly and demonstrate their practicality for use as field mobile power sources.

36

-- --------

CHAPTER NINE

CONCLUSIONS AND RECOMMENDATIONS

The primary objective of this program was to provide USAMERDC with a quantitativeappraisal of the predicted reliability of two organic Rankine-cycle engine generator systems.The tasks performed to meet this objective led to the following conclusions-'

The two manufacturers are constructing generator sets under different powerrequirements. Care should be exercised in making comparisons. The predictive resultsshow little significant difference between the reliabilities of STRATO3's or TECO'sRankine systems.

The electronic control circuits had extremely high failure rates and contributedheavily to system unreliability. TECO is still designing its control circuits; therefore,the STRATOS failure rates were used for the yet undesigned circuits. In this way, theimpact is the same on both manufacturers. When TECO completes its design, theTECO model can be modified.

The failure rates used in this project are estimates based on historical data fromsimilar equipment. Until firm system failure data are developed, the results shouldnot be considered empirical.

The hermetically sealed fluid loops cause the major portion of the generator sets tobe nonfield-repairable. This contributes heavily to system unavailability.

ARINC Research Corporation recommends the following courses of action based on theresults of the analysis:

* Implement a data-collection and feedback procedure for MERDC and the manufac-turer's testing program of the organic Rankine-cycle engine generator set.

Perform a detailed design analysis of the Rankine systems to determine ite best areasfor design improvement, redundancy of components, and repairability to improvereliability, maintainability, and availability.

* Begin developing a life-cycle cost program to evaluate the proposed designs forportable field generator sets against those now in use. The evaluations shouldconsider as a minimum initial production and procurement costs, operational costs,and the effects of repairability, logistics, reliability, and maintainability.Make a critical evaluation of fluidic circuits versus modular-replac3ment electronic

circuits for the Rankine generator sets. The present estimates of control-circuitreliability may make fluidic circuits a wise choice.

37

APPENDIX A

SOURCES OF FAILURE-RATE DATA

APOLLO Reliability Prediction, Estimation, and Evaluation Guidelines, NationalAeronautics and Space Administration, December 1963.

RADC-TR-114, Volumes I, II, and II, Data Collection for Nonelectronic ReliabilityHandbook, Rome Air Development Center, Air Force Systems Command, Griffiss Air ForceBase, New York, June 1968.

Failure Information Notebook, Special Technical Report No. 32, ARINC ResearchCorporation, December 31, 1965.

Mechanical Design and System Handbook, Harold A. Rothbart, McGraw-Hill BookCompany, New York, 1964.

MIL-HDBK-217A, Reliability Stre-s and Failure Rate Data for Electronic Equipment,Department of Defense, 1 December 1965.

Army, Navy, Air Force and NASA FARADA Failure Rate Data Program, Volumes 1, 2,3, and 4, Naval Fleet Missile Systems Analysis and Evaluations Group, Corona, California.

A-I

APPENDIX B

COMPUTER PROGRAM FLOW CHART AND INSTRUCTIONS FOR USE

FLOW CHART

The flow chart for the computer program is presented in Figure B-1.•

INSTRUCTIONS FOR USE ON TIME-SHARING COMPUTER TERMINAL

The steps described herein must be strictly adhered to for the program to functonproperly.

When a link with the time-sharing system is established, the first symbol seen after"RUN" is typed is an equal(=) sign., After the equal sign, type the number of components(N) in the system and the number of cycles of operation (M) (ten maximum). Each of thesevariables is allocated two places, and the datz must be right-justified.

A second equal sign will then appear, and the M sets of times of operation must betyped. Each set consists of two times, a startup time and a run time, in units of hours. Eachtime is allocated five places; it must be typed with a decimal place and in such a way tibatnone of the five-digit fields overlap.

The third and last equal sign will appear, and the K-factor codes (1 to 4) must then bepunched for the M cycles of operation. These factors are used to adjust the failure rate andmean values. There must be K factors for both startup and run; each K factor is punched inan 12 format This ends the data entry at the keyboard at the time of execution.

The failure rates, means, accrued operating time, and K factors are stored as file andcalled "XRDATA" for FairchildiStratos and "YRDATA" for Thermo Electron., Beforerunning the progrim (XMODEL), it is necessary to type the following line if the data file forFairchild/Stratos is to be used: 90 READ ("XRDATA", 4) (ISP(l, 1), ISP(I, 2) IDST(I),(VAR(I, 4 J = 1, 7), I = 1, N),

The term XRDATA must be changed to YRDATA if the Thenno Electron data file isused.

When the data are prepunched, the following format is used, where one line representsone component:

Columns 1-5 contain a line number code. This is not used. by the model program butis used to edit and update data entries.

B-1

'0x=- I

-_ I /t

-t I

S•/ < - - < = i , "

• --------J <-- --- - - - -'A J,• Ii

Column 8 contains a "1" if the component is in series and a "2" if it is in parallel.

"Column 11 contains a "1" if the component is used in startup only, a "2" if it is usedduring run only, and a "3" if it is used for both phases.

Column 14 contains the distribution codes:

1 = exponential2 = normal3 = lognormal4 = probability of success

"Columns 15-21 contain the exponeniial failure rate X 106, or the mean. time tofailure (normal or lognormal), or the probability of the component's success.

* Colunms 22-28 contain the standard doviation (normal or lognormal) or are set to 0.

"Columns 29-35 contairn the time the component has already operated if normal orlognormal is used or are otherwise set to 0.

"Columns 36-42 contain K factor number 1.

* Columns 43-43) contain K factor number 2.

Columns 50-56 contain K factor number 3.

Columns 57-63 contain K factor number 4.

Note 1.' The last seven fields must be punched with a decimal point, and no fields mayover!ap.

Note 2: The values associated with iograurmally distributed variables must be in terms ofnatural logarithms.

The prediction program iE shown in Figure B-2.

B-3

Ii )IN. 1513C,~ 1S~75.2) p 1LT(7!3),PVAR(C75v 7). *1( 2U) I OFC2U)

KEAU I PNmN

'I % c: 11 U v T I I a

60 2 FOiRMAT( IOF*5e0)

H) 3 FuliA(2012 )

10.1 4 F0N%.AlCbxo3I3p7F7.2)111) A-14~0 SYSTEN' RELIABILITIESA ANJD PHASE OP~EN* TIME"I12o S=1 .0I 3,j D 1) 0I I I

:lo ~ U ,I 0 1F( 1(,)2 20,1,

I (- I.

J11CI (vi-) ( b,2b,23c

3.0 IF'CII ) 2I).2t,23

310 ~ C 25 = l 2IMFIA)IAc10239'~~ 26,k=j~C,

350 IF(X T 200'!U2

4'3SO I0 U.)JTIJU.,.370

39 :40 v = VOHATk(CEI,.I

4~(J PHP'T 8.21)5

4A) 0 9 F'2iMAT(3EI b-8)

471.)S410j E 4JU

Figure B-2. PREDICIION PROGRAM