Math Model And Simulation In Automobile Air Conditioning System

With the development of automobile industry, more and more manufacturers and users regard automobile air conditioning system as an important part of automobile, because automobile air conditioning system is necessary for the comfort of it. Researching the dynamic properties of refrigeration system is a focus among the international refrigeration academic. With the help of numeric simulation technique, we can analysis the system's steady state and dynamic performance and the methods of optimization, these are very important in theory and application fields. Aimed at the existed questions and researched status in automobile air conditioning system, this paper accomplished the following issues: First, this paper constructs a general model of refrigerant thermodynamic properties calculation for simulation of refrigeration and air condition system based on the parametric equations of state of refrigerant. The module has good property of extension and opening. Using R12, R22, R134a, Compared with the data provided by the standard graphs and tables of refrigerant thermodynamic properties, the calculation results of this model have certain precision and fast calculation velocity, and can meet the requirements of simulation of automobile air conditioning system. Second, as central part of refrigeration system, there's direct connection between performance of compressor and energy exhaust,noise,reliability and flexible fixing. This paper use two-working area slip compressor as research object and math model is established. To established model simple analyze is finished. Third, a general dynamic distributed model of heat exchangers (evaporator and condenser) is constructed. This model is described by Lagrange method. Base on the calculation method of tracing the little mass of liquid, a simulation model is set up. The characteristic of static and dynamic state about evaporator and condenser is researched, which Working medium is R134a. Through simulation and analyze the result, dynamic changing of performance parameter of heat exchanger can be reflected excellent. The result is consistent with thermodynamic theory and practice working process of heat exchanger.