Abstract: Based on the geometric parameters of heat pump scroll compressor, first law of thermodynamics, the laws of conservation of mass and energy and so on, the geometric model and thermodynamic model of the heat pump scroll compressor were established in this paper, and the method of Euler was used to solve this model, then the changing trend of temperature, pressure and mass of working fluid in the working chamber of compressor were obtained. The leakage changing law of the heat pump scroll compressor under different working conditions was analyzed. Finally, the established thermodynamic model was verified by building a test platform. The results show that the suction pressure and temperature have the greatest influence on the compression chamber. When the suction pressure decreases by 0.1 MPa, the leakage of the third compression chamber decreases by 9.45%. When the suction temperature decreases by 5 ℃, the leakage of the third compression chamber decreases by 6.841%. While the influence of speed change on the leakage of each working chamber of scroll compressor is average, and the experiment values are close to the simulation values, which verifies the correctness of the model. The research in this paper provides a some theoretical reference for the performance optimization of the scroll compressor of heat pumps.

Key words: heat pump scroll compressor, thermodynamic model, operating parameters, experiment verification