The Research And The Improvement On Air Conditioning System Refrigeration Performance Of A Passenger Car

With the continuous development of the automotive industry,it is getting more and more concerned about the comfort of the cars by customers.The automobile HVAC,as one of the main comfort figures of the automobile,has become the inevitable factor for researchers to develop the comfort of current automobiles.Through the CFD and the Environment simulation test,this paper which focuses on developing the refrigeration effect of the car HVAC of a particular brand,puts forward an improving design scheme for HVAC and achieved satisfactory results.The improvement of refrigeration system of a new type of car,which is developed by the author's current company,is taken as research object in this paper.To calculate the target value of monomer components in refrigeration system through the calculation methods of air conditioning load in automobile refined by the author's current company,the following aspects have been presented in this paper.They are introducing the HAVC theory,as well as benchmarking the overall air conditioning environment simulation test conclusion and the overall expected value of air conditioning system refined by the author's current company.This paper also presents the preliminary design and selection of components,the process to achieve the capacity data through the CFD simulation analysis and the monomer components,as well as obtain the preliminary evaluation of vehicle cooling effect through environmental simulation experiment.The CFD and environmental simulation experiment showed that the refrigeration effect can't achieve the overall target,even though the monomer components meet the indicators.Theoretical analysis is implemented before optimizing the system.And then,the paper presents the particular optimization of HVCA,after predicting the transmission loss according to the CFD simulation of the main HVAC components such as flow flux,airflow distribution,surface velocity distribution,pressure distribution,pressure drop and the flow trace,etc..An improving schema of related components of refrigeration system in the prototype phase is proposed according to the temperature rising conditions at different time in the complete vehicle climate stimulation test.Thus,optimizing the structure and stepping up the targets of main refrigeration components,suchas condenser,evaporator,blower and compressor,etc.are discussed in this paper.After the optimization of monomer components,this paper presents the CFD simulation and performance testing of each optimized components to ensure the monomers meet the expectation and all the optimized parts meet the requirement.Finally,the expected overall refrigerating effect of each monomer component is guaranteed.Proven by the simulation test and the monomer test,the components of the optimized system are sequential combined loaded.After loaded,the combination is processing the environmental simulation test provided by the author's current company.The temperature statistics of eight cabins getting from the test are used to point out the best upgrading scheme containing the figures shown above.Furthermore,the scheme achieves a significant reduction in the temperature of 7.7degrees Celsius under engine idling speed,so as to achieve the purpose of improving the efficiency of air conditioning refrigeration.