Development Of Air Conditioning Unit Performance Testing Equipment For Rail Vehicles

With the rapid development of economy in our country, according to the characteristics of dense population, rail transit had been got rapid development with its low operating cost, large transport capacity. But with fast development of rail transit in our country, it brought the corresponding problems: the construction and manufacturing facilities of urban rail transit. Therefore, it is the important premise of rail transit development in our country to construct our country characteristics of urban rail infrastructure. In this paper, it is using the air conditioning unit testing of rail transit in Chongqing as the background. The complete set of testing equipment using in air conditioning unit has been designed to meet the Chongqing rail transit. The testing equipment mainly include: Air conditioning unit cleaning bench, Air conditioning unit idle testing bench, air conditioning unit performance testing bench.The testing equipment has different forms because of different forms of the air conditioning unit. Therefore, the structure of air conditioning unit has been analyzed firstly. Then the advantages and disadvantages of existing cleaning bench, air conditioning unit idle testing bench and air conditioning unit performance test bench had been contrasted and analyzed. So the forms of three testing bench had been determined, according to the actual situation of a certain line of Chongqing rail transit.According to the working principle of three kinds of testing bench, the structure of three kinds of testing bench has been designed, and using the SOLIDWORKS to draw the structure of the three kinds of testing bench and to simulate the feasibility of three kinds of testing bench. Then using CFD to simulate removable exterior environment simulation room and confirming the feasibility of removable exterior environment simulation room.The three kinds of testing bench had been successfully completed according to the design size of testing bench. And the accuracy of three testing bench were measured. The air conditioning unit cleaning bench has the advantages of high cleaning efficiency and less labor. The current and voltage measurement errors of three motor measured by air conditioning unit idle testing bench are less than the measuring error given by air conditioning unit manufacturers. The experiment result showed that exterior environment simulation room construction cost savings of 50% by using removable room. Its room temperature has high accuracy and stability by using air of air conditioning unit and exterior air, which can save 50%-60% energy consumption. The accuracy of testing bench is less than 4%, which is better than the national standard GB/T 19842-2005.Finally, the air enthalpy difference method is used to measure the refrigerating capacity of air conditioning unit. Its uncertainty had been analyzed and calculated. The calculate result showed that air conditioning unit imported enthalpy, export enthalpy and air volume have higher influence to the refrigerating capacity of air conditioning unit. Thus it can be have the conclusion that the testing bench needs to improve the precision of the parameters related to imported enthalpy, export enthalpy and air volume in order to improve the precision of air conditioning unit’s refrigerating capacity using air enthalpy difference method.