6-3 heat engines (热机)Heat sources,THQinWnet,outHeat enginesoutHeat sink, T
6-3 heat engines (热机) Heat sources, TH Heat sink, TL Qin Qout Wnet,out 11 Heat engines
6-3 heat engines (热机)一一steam power plantHeatsources,TEnergy source(suchasafurnace)SystemboundaryQinQinBoilerWoutHeat enginesW.PumpTurbinenet,outCondenseroutQoutEnergysink(suchastheatmosphere)Heat sink, T
6-3 heat engines (热机)－－steam power plant Heat sources, TH Heat sink, TL Qin Qout Wnet,out 12 Heat engines
6-3 heat engines (热机)一一steam power plantQinheatsuppliedtosteaminEnergy sourceboilerfromheatsource(suchasafurnace)(furnace)System boundaryQinQoutheat rejected from steamBoilerin condensertoheat sink(atmosphere or a river)WoutW.PumpTurbineWoutwork delivered by steamin turbineWin-workrequiredtoCondensercompresswatertoboilerCoutpressure.Energy sink(suchastheatmosphere)Wnet,out=Wout-WinCombined systemcan be analyzed as a closed system;Wnet,out=Qin-QoutHeat engine is a closed systemin a cycle: △U=0;13
6-3 heat engines (热机)－－steam power plant • Qin—heat supplied to steam in boiler from heat source (furnace) • Qout—heat rejected from steam in condenser to heat sink (atmosphere or a river). • Wout—work delivered by steam in turbine • Win— work required to compress water to boiler pressure. • Wnet,out=Wout-Win Combined system can be analyzed as a closed system; Heat engine is a closed system in a cycle: 13 Wnet,out=Qin △U=0; -Qout