Test Bank for Modern Refrigeration and Air Conditioning, 21st Edition by Althouse, 9781635638776, Covering Chapters 1-55 Includes Rationales

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REFRIGERATION AND AIRC
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ONDITIONING




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, B.TECH. DEGREE COURSE
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SCHEME AND SYLLABI
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(2002-03 ADMISSION ONWARDS)
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MAHATMA GANDHI UNIVERSITY
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KOTTAYAM,KERALA


REFRIGERATIONgANDgAIRgCONDITIONING
Mg703ggggggggggggg 2+1+0
Moduleg1

Principlesgofgrefrigeration:gThermodynamicsgofgrefrigerationg-
gCarnotgcycle,greversedgcarnotgcycle,gheatgpump,gandgrefrigeratinggmachine-


gcoefficientgofgperformanceg-gunitgofgrefrigerationg-grefrigerationgmethods-


gconventionalgrefrigerationgsystems.gAirgrefrigerationgsystem-


gBellgColemangcycleg-


gC.O.P.gcapacitygworkgandgrefrigerantgflowgrequirementsgingBellg-


gColemangcycle.




Moduleg2

Vapourgcompressiongsystem:gsimplegcycleg-comparisongwithgCarnotgcycleg-
gtheoretical,gactualgandgreactiveg-gCOPgeffectgofgoperatinggparametersgongCOPg-


gwet,gdrygandgsuperheatedgcompressiong-gundergcoolingg-


gactualgcyclegrepresentationgongTSgandgPHgdiagramsgsimplegproblems.gAdvanc


edgvapourgcompressiongsystemsg-gmultistagegvapourgcompressiongsystemsg-
gflashgchambergmultiplegcompressiongandgevaporationgsystemsgcascadingg-


gsimplegproblems.




Moduleg3

Vapourgabsorptiongsystems:gsimple,gcyclesg-gactualgcycleg-
gammoniagwatergandglithiumgbromidegwatergsystemsg-gCOPg-

gelectrolux gsystem.gRefrigerantgandgtheirgproperties: gNomenclatureg-

gsuitabilitygofgrefrigerants gforgvariousgapplicationsg-

gunconventionalgrefrigerationgmethods-gVortexgtube,gsteam-

jet,gmagneticg(cryogenics)grefrigerationgandgthermoelectricgrefrigerationg-


2

, gappliedgrefrigerationghousegholdgrefrigeratorsg-
gunitgairgconditionersgandgwatergcoolersg-gicegplantgcoldgstorage.

Moduleg4

Refrigerationgsystemgcomponents:gcondensersg-
gwatergandgairgcooledgcondensersg-gevaporativegcondensersg-


gexpansiongdevisesg-gcapillarygtube-gconstantgpressuregexpansiongvalveg-


gthermostaticgexpansiongvalveg-gfloatgvalvegandgsolenoidgvalveg-gevaporatorsg-


gnaturalgconvectiongcoilsg-gfloodedgevaporatorsg-


gdirectgexpansiongcoils.gReciprocatinggcompressors:gsinglegstagegandgmultistag


egcompressorsg-gworkgdonegoptimumgpressuregratio-geffectgofginterfoldingg-
gvolumetricgefficiencyg-effectgofgclearanceg-


gisothermalgandgadiabaticgefficiencyg-


gcompressedgairgmotors.gRotodynamicgcompressors:gScrewgandgvanegtypegcom


pressorsg-gprinciplegofgoperationg-
ghermetic,gsemihermeticgandgopengtypegrefrigerationgcompressors.




Moduleg5

Principlesgofgairgconditioning:gPsychrometrygandgpsychrometricgchartgthermod
ynamicsgofghumangcomfortg-geffectivegtemperatureg-
gcomfortgchartgappliedgpsychrometryg-gsensiblegheatgfactorg-

gpsychometricgprocess-

problems.gWintergairgconditioning:gheatinggloadgcalculationsghumidifiersgandgh
umidistat.gSummergairgconditioning:gcoolinggloadgcalculationsg-
gyeargroundgairgconditioningg-gunitarygandgcentralgsystemsg-

gprinciplesgofgairgdistributiong-gdesigngofgairgductgsystems.




References


1. Refrigerationgandgairgconditioningg -g BallaneygP.gL.
2. Refrigerationgandgairgconditioningg -g StockergW.gF.
3. Refrigerationgandgairgconditioning -g JordangandgProtester
4. PrinciplesgofgRefrigeration -g RoygJ.gDossat




3

, MODULE – I g g




Air Refrigeration Cycles
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1.1 gIntroduction
Ingangairgrefrigerationgcycle,gthegairgisgusedgasgagrefrigerant.gIngoldengdays,gairg
wasgwidelygusedgingcommercialgapplicationsgbecausegofgitsgavailabilitygatgfreegofgcost.g
Sincegairgdoesgnotgchangegitsgphasegi.e.gremainsggaseousgthroughoutgthegcycle,gtherefor
egthegheatgcarryinggcapacitygpergkggofgairgisgverygsmallgasgcomparedgtogvapourgabsorbin
ggsystems.gThegair-
cyclegrefrigerationgsystems,gasgoriginallygdesignedgandginstalled,garegnowgpracticallygo
bsoletegbecausegofgtheirglowgcoefficientgofgperformancegandghighgpowergrequirements.g
However,gthisgsystemgcontinuesgtogbegfavouredgforgairgrefrigerationgbecausegofgtheglowg
weightgandgvolumegofgthegequipment.gThegbasicgelementsgofgangairgcyclegrefrigerationgs
ystemgaregthegcompressor,gthegcoolergorgheatgexchanger,gthegexpandergandgthegrefrigerat
or.

Beforegdiscussinggthegairgrefrigerationgcycles,gwegshouldgfirstgknowgaboutgtheg
unitgofgrefrigeration,gcoefficientgofgperformancegofgagrefrigeratorgandgthegdifferencegbet
weengthegheatgengine,gagrefrigeratorgandgagheatgpump.

1.2 UnitsgofgRefrigeration
Thegpracticalgunitgofgrefrigerationgisgexpressedgingtermsgofg‘tonnegofgrefrigerati
on’g(brieflygwrittengasgTR).gAgtonnegofgrefrigerationgisgdefinedgasgthegamountgofgrefrige
rationgeffectgproducedgbygtheguniformgmeltinggofgonegtonneg(1000gkg)gofgicegfromgandga
tg0oCging24ghours.

Sincegtheglatentgheatgofgicegisg335gkJ/kg,gthereforegonegtonnegofgrefrigeration,

ITRg=g1000g×g335gkJging24ghours

1000  335
=g = 232.6 kJ/min
24  60




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