带经济器螺杆制冷循环系统的研究

STUDY ON SCREW REFRIGERATION SYSTEM WITH AN ECONOMIZER

从带经济器螺杆制冷循环系统的工作机理山发,本文分析了现有理沦模型的缺陷,导出了新的数学模型。并具体分析、求解了R717、R22、R12、R502等四种常用工质、经济器传热温差、螺杆压缩机泄漏和喷油等实际因素对带经济器制冷机性能的影响。实验验证了该模型的正确性,同时肯定:制冷系统增设经济器以后,在所测试的工况范围内,其性能明显提高。例如,当t_o=-35℃,t_k=40℃,工质为R717时,制冷量增加24.1％,制冷系数提高19.5％。

Through studying the working mechanism of screw refrigeration system with an economizer(SRSE), this paper analyses the drawbacks of the theoretical models now available, and presents a new mathematical model. The effects on the performance are studied of the commonly-used refrigerants R717, R22, R12 and R502, temperature difference of heat transfer in the economizer, and the leakage and oil-flooded in screw compressor, etc. Experiment verifies the reliability of the new model, and makes sure that the performance of SRSE is greatly improved within the test range; e. g., △Q_0/Q_0= 0.241, △K_e/K_e= 0.195 at t_0= -35℃ and t_k= +40℃ for R717.