chapter7CompressorandTurbine

7-1ClassificationofCompressorcompressorPositivedisplacementTurbinereciprocatingrotarycentrifugalaxialflowThisisthetypewewillstudy

7-2CompressorWork7-2-1Thecycleofcompressorpv

7-2-2CompressorWork

IfisothermalIfisentropicIfpolytropic

pvIsothermalPolytropicIsentropic

7-3Realcompressor7-3-1Clearancevolume

7-3-2TheeffectofClearancevolumepv

7-4MultistageCompressionwithIntercoolingpvp1p2pmBA

Sincep1v1=pmvm

TogettheminimumworkThen:

7-5SteamTurbine7-5-1SteamTurbine

7-5-2h-sDiagramhscp1p2T1T2vX=0.8constantpressurecurves(2)Isothermalcurves(3)constantspecificvolumecurves(4)constantdrynessfractioncurvesX=1X=0.6X=0

7-6AdiabaticEfficiencyofSteady-FlowDevices7-6-1CompressorIfanadiabaticcompressor:

12Drawtheprocessonah-sdiagramButiftheprocessisanirreversibleprocess,itwillbe:hsP2P1w2’w’Thereforewedefinetheinnerefficiencyofcompressorasfollowing:Thisequationcanalsobeusedforpump

7-6-2TurbineIfanadiabaticturbine:21hsP1P2ww’Thereforewedefinetheinnerefficiencyofturbineasfollowing:2’ThisequationcanalsobeusedfornozzleIfirreversible:

Theendofthischapter