通过对制冷系统循环特性、变工况特性和参数间耦合特性的分析,遵循热力学基本定律和能量、动量、质量守恒定律,采用稳态和动态建模相结合的方法建立压缩式制冷系统的数学模型.针对换热器建模难点采用分相区和移动边界相结合的方法建立其集总参数动态模型,并且冷凝器与高压储液器相结合,构成冷凝器加储液器的整体部件,文中建立的制冷系统的整体模型,反映了制冷系统工况变化时制冷剂质量的重新分配及其对状态变量的影响,提高了系统建模的精度,最后通过实验对所建模型的准确性进行了验证.%Firstly, cycle characteristics, variable condition characteristics and coupling characteristics between parameters of the refrigeration system were analyzed. Next, basic laws of thermodynamics, energy conservation, momentum conservation, and mass conservation were followed. Then, using combination methods of steady state and dynamic modeling, the paper established a model of compression refrigeration system. Steady - state models of compressor and electronic expansion valve compared with heat exchangers with moving boundary, lumped parameter models of evaporator and condenser were established. Different dynamic mathematical models were established for high pressure liquid receiver, which is combined with condenser. The proposed model of the refrigeration system reflects the refrigerant mass redistribution and its impact on other components ( state variables) , which improve the accuracy of system modeling. Experiments show the accuracy of the model.
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