The Model Optimization Of Heat Exchanger And Refrigeration System In Air-Conditioner Digital Design

At present, heat pump air conditioning has been attracting more and more consumers in markets and spread and applied gradually by taking advantage of energy-saving, less pollution, high degree of automation and refrigeration in summer and heating in winter. China is one of the main markets in the world, and more than 70 percent production capacity is in China. For corporation producing air-conditioners, how to use computer programming to research the design and operation of household air conditioning system and how to achieve the optimum matching of the whole system from the perspective of basing theory analysis and depending practical operation has become an important development direction. To some extent, digital simulation replaces the real systematic experiment consuming much time and money, and shortens the period of product updating so as to meet the market need. Based on the background, this paper uses computer simulation of air conditioner to realize the steady state performance simulation of household air conditioning system.This thesis firstly perfects the physical properties calculation program of refrigerants and put forward the new fast and explicit calculation model of refrigerant R22. This model need no iteration and can shorten simulation time. Secondly, it sets up the compressor model and heat-exchangers model. These models improve the precision and broaden the application range, thus meet the need of system simulation.The thesis establishes calculation model of household air-conditioning system simulation based on the component models, improves the past iterative algorithm and the stability of system steady simulation algorithm. Compared with experimental data, there is a close match between the simulation results and the experiment results. The model can be used to simulate the running of the system and estimate the performance of the system. Meanwhile, it also makes some operation performance analysis in systematic variable working conditions. A kind of software of air-conditioning digital simulation and performance analysis system is established with Visual C++ based on the system simulation numerical model. Numerical models for air-conditioning system, including models of refrigerant and air physical property and different components, are defined as different classes. The software was developed by the object-oriented technology and is convenient for user to learn and secondary development.