运用两级喷射式制冷提高客运汽车空调性能的理论与实验研究

1、运用两级喷射式制冷提高客运汽车空调性能的理论与实验研究The current world situation of an increasing population is leadingto an increase in the fuel consumption, green house gas emissions,electricalpower consumptionetc.These increases are becoming a seriousproblem which various organizations are concerned about and are tryingto

2、 solve. An increase of bus air conditioning systems increases fuelconsumption and therefore produces green house gas emissions asconventional bus air conditioners are vapor compression systems drivenby engine power. In order toreducethe fuelconsumptionand gas emissionofa bus, a two stageejectorcooli

3、ngsystem isselectedto studybecausethesystem requires littleelectricalpower orengine power to drive thesystem. It uses exhaustgas emissions frombuses to drive. The twostageejector cooling system is used to cool condensate from the condenser ofa bus air conditioner to a subcooling state in order to en

4、hance theperformance of vapor compression system.The objective of this researchis to study in theoretical and experimental performances of a two stageejectorcooling system usingthe waste heat of the engine (exhaustgases).To develop a combined air conditioning system with a two stage ejectorcooling s

5、ubsystem and a vapor compression subsystem and evaluating theapplications of a two stage ejector cooling system to enhance theperformance of the traditional bus air conditioning (vapor compressionsystem).The coolingcapacityobtainedfrom thetwo stageejectorcoolingsubsystem is in turnused to cool the c

6、ondensate of the vapor compressionsubsystem to a subcooled stateto increase the COPof the vapor compressionsubsystem. The ejector cooling system uses water as the working fluid;the design operating conditions have a generating temperature of150,a condensing temperature of54 and an evaporatingtempera

7、tureof13 , Inthis work, variables were tested in order to understand the applicationofthe system and the effect of varyingoperatingconditions.Inaddition,thecomparison of theperformance between the single stageand two stageejector cooling system has been carried out.The results indicate that atwo sta

8、ge ejector cooling system can decrease the temperature of thecondensate from the condenser from54 to26.5 under operatingconditionswith a generating temperature of150 and an evaporating temperatureof21.7 , of which the COPejc is0.37. If condensate from the condenserof a vapor compressionsystem is coo

9、led by the two stage ejector coolingsystem under these conditions, the liquid becomes a subcooled stateat26.5 , the COPVCS improves from3.6to4.85(+34.86%). Furthermore, inthis study, under high evaporating temperature condition, the two stageejectorsystem had lower performance than thatof the singlestage ejectorsystem. The two stage ejector system showed better performance than thesingle stage ejector when used at a low evaporating temperature.Theexpected advantages of the proposed system are reduced fuelconsumption,redu