Thermodynamics Lab Report

Weighting:15%ofthetotalmarksforthiscourse.Thisissubdividedasfollows: Labs1&2:10%(Thisreport–Completedinyourowntime) Labs3&4:5%(Completedduringthelabtime)

Pleasecompletethelaboratoryexercisesandsubmitareportcombininglabs1and2. The

reportshouldbe producedwitha wordprocessorsuchas MicrosoftWord.Althoughlaboratory workwillbedoneingroups,eachstudentmustsubmittheirownindividuallaboratoryreport.

Laboratories1and2:Internalcombustionengineefficiency

Youarepartofanengineeringteamthatis developinga trickleirrigationsystemfor agriculturalpurposes.Thesystemconsistsofa25000Lwatertankonastandwhich is13mhighandapetrolordieselpoweredpumptopumpthewaterfromadamup intotheelevatedtank(Fig.1).Yourtaskistoreportontheexpectedperformance (from a thermodynamicspoint of view) of some available motor and pump combinationsforthesystem.Youmustbaseyourconclusionsonexperimentaldata youhave collectedfromthe laboratory.Therangeofchoicesunderconsiderationhas beennarrowedto threepumpsandtwoengines.Oneoftheenginesisa232ccfour- strokedieselmotorandtheotherisa172ccfour-strokepetrolmotor.Theseengines arelocated inthemechanical engineering labatGriffithUniversity alongwithtest beds and dynamometers which you will use to measure their performance and simulatetheloadthatwouldbeplacedonthemotorbythepump.

25kL2m

13m

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Dam

Pumpandmotor

Fig.1 Systeminwhichmotoristobeused Comment by abdullah: Use this graph in the report

AnotherengineerontheteamhasanalizedthepipingsysteminFig.1(youwilllearn howtodothiswhenyoustudyfluidmechanics)andhasfoundthatiftheflowrate,Q

(m3/s)isdecidedthentherequireddifferenceinhead(metersofwater)betweenthe inletandoutletofthepumpfollowsthefollowingequation(Note:multiplyhpumpby(ρg) togetpressuredifferencebetweenpumpoutletandinletinpascals):

hpump

=15+1.2 Q2

D4

(1)

Thisequationisusuallycalledthe‘systemcurve’.Itisuniqueforeachpipesystem.It isdifferentdependingonthelengthanddiameterofthepipe,thepipefittingsselected forthesystemandthedifferenceinelevationbetweenthesupplywaterandtank.Dis

theinletdiameterofthepipe(inmeters)andQistheflowrateinm3/s.Q2/D4appears

intheequation because losses inapiping system areusually proportional tothe squareofthewatervelocityinsidethepipe. Theengineersuggestsa pipewithinside diameter D=35mm=0.035m.

Fig.2showsthecharacteristic perfomance curvesforthreedifferentpumpsbeing considered:PumpA,PumpBandPumpCsuppliedby themanufacturer.Thecurves showthedifferencein headsuppliedbythepumpforanygivenflowrate.Efficiencies listedinFig.2aremechanical efficienciesforthepump.IfyouplotEq.(1)onthe graphshownin Fig.2,thepointswhereEq.(1)interceptsthecharacteristiccurvesfor pumpsA,BandCwillshowtherequiredoperatingconditionsforyourmotor.

CentrifugalPumpCharacteristicCurvesat 2400rpm

PumpA

Efficiency

( P u m p h e a d )PumpB

PumpC

Flowrate

Fig.2Pumpcharacteristiccurves Comment by abdullah: Use this graph in the report

UsingFig.2,Eq.1andtheequipmentavailablefortestingtheinternalcombustion enginesinthelab,youarerequiredtosupplythefollowinginformation:

1. ThenoiseindBmadebyeachofthe motors(measuredinthelaboratory).Notealso thelocationwherethenoisemeasurementwasmade.

2. ThedutypointsforpumpsA,BandC(i.eflowrate,headandpumpefficiency

correspondingtowhereEq.(1)intersectsthecharacteristiccurvesshowninFig.2).

3. Thepower(andtorque)requiredtoturntheshaftofthepumpateachofthethreeduty points.

4. Whetherornottheenginesinthelabarecapableofdeliveringenoughpowertorun thepumpsateachofthedutypoints.

5. Thethermalefficiencyoftheenginesateachofthethreedutypointsatthespecified rpm(measuredinthelaboratory)

6. Timeneededtofillthe25000Lwatertankforeachpump/motorcombination.

7. No.oflitresoffuel(andapproximatecost)requiredto fillthe25000Ltankforeach pump/motorcombination?

8. Theincreaseinpotentialenergyof25000Lofwaterasmovesfromthedamtothe tank.

9. Theenergyusedbythemotorinfillingthewatertankforeachpump/motor combination.

10.Theoverallthermalefficiencyofthesystem(uselowerheatingvalueforthefuel).

11.Theair/fuelratioattheconditionstested.

12.Thenumberofkgofcarbondioxidereleasedtotheatmospherebyfillingthetankfor eachpump/motorcombination.

13.Arecommendationasto thebestpump/motorcombinationforthispurposeandan explanationofwhyyouaremakingthisrecommendation.

14.Anysuggestionsofhowtheefficiencyofthesystemmaybeimproved.

ReportFormat

ItisexpectedyourreportwillbetypedusingawordprocessorsuchasMicrosoftWord (apartfromrawdataandanyhandwrittencalculationsthatyoumayincludeinthe appendix)andwillcontainthefollowingsections:

Title:

Name&Date:

Summary: Brieflydescribe(approximatelyhalfapage)thepurposeofthereportandthemain findingsofyourinvestigation.

Equipment: Includephotograph(s)oftheapparatusused

Results: Youshouldsummarizeyourresultsinatablesuchasisshownbelow:Table1: Results. Youshouldexplainbrieflyhowyourcalculationsfor both Petrol and Dieselweredoneincludingany assumptionsyouhavemade.Youshouldalsoincludeagraphoftheexperimentalresults fromthelabshowingtheefficienciesoftheenginesfordifferentloads(i.e.thermalefficiency oftheengine(verticalaxis)againstpoweroutput(horizontalaxis)). Comment by abdullah: The calculation should be for both petrol and diesel in separated paragraphs and include the graph of the efficiencies for both.

ConclusionsandRecommendations: Hereyoushouldgivearecommendationastothe bestpump/motorcombinationforthispurposeandanexplanationofwhyyouaremakingthis recommendation.Youshouldalsoincludeanysuggestionsofhowtheefficiencyofthesystem maybeimproved.

Appendix1:RawData Thissectionshouldcontaintherawdatayoucollectedinthelab

Appendix2:SampleCalculations Thissectionshouldcontainoneofthefollowing:

• handwrittensamplecalculations

• oraprintoutfromaspreadsheetthatyouusedtodoyourcalculations(withformulae displayed)

• oraprintoutofacomputerprogramcode(e.g.Matlab)thatyoumadetodoyour calculations.

( E n g i n e: D i esel P e t r o l N o i s e (d B ) : P u m p : A B C A B C F l o w r a t e ( k g / s ) * : ( w a t e r ) P u m p H ead ( m ) * : P u m p E ff i c ie n c y * : R P M * : P o w er R e qu i r ed f r o m mo t o r ( k W ) * : T o r q u e R e qu i r ed f r o m mo t o r ( N . m ) * : C ane ng i n e d e l i v er r e qu i r ed p o w e r ? T h e r m al e f f i c i e n cy o fe n g i n e ( % ) T i m e n ee d ed t o pu m p25000L o f w a t er N o . o fli t r es o f fu el r e qu i r ed t o p u m p 25000L o f w a t er ( L ) C o st o f fu e l r e qu i r ed t o p u m p 25000L ( $ ) I n c r ease in pot e n t i a le n e r g y o f 25000L o f w a t er ( J ) E n e r g y u sed b y m o to r t o f ill t h e t a n k ( J) Ove r all th e r m al e f f i c i e n cy o f th e s y s t em A i r / Fu el R a t i o : Mass o f C O 2 p r o d u ced b y pu mp i n g25 0 00 L o f w a t er ( k g) : R ec o mm e n d ed pu mp / m ot o r c o m b i n a t i on : )Table1:Results Comment by abdullah: From this and onwards all are the raw data , some been completed and some few missing and only table 1 that needs calculating .

*Thesecorrespondtothedutypointsandshouldbedeterminedbeforedoingthelab.

Pleaseincludethefollowingtablesasanappendixinyourreportwithyourenginetestresults foreachengine.

Dateoftest:	17/08/14
Timeoftest:	11:00am
TestbedserialNo.	TQ111869-003
EngineserialNo.	TQ111979-01
Enginetype	Diesel
Enginesize(Litres)	0.232
No.ofstrokes	4
Fueltype	Diesel
Fueldensity(kg/m3)
Fuelcalorificvalue(kJ/kg)
Ambientairpressure	1011mbar
Airboxorificedimensions(m)

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		DieselEngine	Fuel	AirandExhaust
	Meas.No.	Engine speed (rpm)	Engine torque (N.m)	Engine output power (W)	Fuel volume (mL)	Fuel drain time (s)	Ambientair temperature (°C)	Exhaustgas temperature (°C)	Airbox differential pressure (Pa)
	1	2320	2.4	580	8	85	22	146	-350
	2	2405	2.7	690	8	79	22.2	167	-340
	3	2360	3.7	920	8	70	22.2	172	-325
	4	2360	5.2	1290	8	59	22.3	199	-305
	5	2370	6.1	1510	8	53	22.5	224	-290
	6	2300	8.0	1910	8	44	22.9	240	-275

Dateoftest:	18/08/2014
Timeoftest:	10:20am
TestbedserialNo.	TQ111869-004
EngineserialNo.	TQ117203-001
Enginetype	Petrol
Enginesize(Litres)	0.172
No.ofstrokes	4
Fueltype	Petrol
Fueldensity(kg/m3)
Fuelcalorificvalue(kJ/kg)
Ambientairpressure	1011mbar
Airboxorificedimensions(m)

8

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		PetrolEngine	Fuel	AirandExhaust
	Meas.No.	Engine speed (rpm)	Engine torque (N.m)	Engine output power (W)	Fuel volume (mL)	Fuel drain time (s)	Ambientair temperature (°C)	Exhaustgas temperature (°C)	Airbox differential pressure (Pa)
	1	2390	2.3	598	8	68	23.4	265	-10
	2	2368	3.2	785	8	62	24	324	-22
	3	2380	4.2	920	8	55	24.3	356	-30
	4	2340	4.9	1200	8	52	24.5	394	-45
	5	2340	5.9	1450	8	49	24.7	405	-52
	6	2250	9.0	2050	8	36	23.3	471	-90