热泵用双螺杆制冷压缩机冷却方式的试验研究.pdf

热泵用双螺杆制冷压缩机冷却方式的试验研究 热泵用双螺杆制冷压缩机冷却方式的试验研究 吴华根李建风邢子文束鹏程 (西安交通大学能源与动力工程学院710049西安) 摘要 目前，风冷热泵应用中存在着压缩机排气温度过高，电机温度偏高等不利条件，因此也影响了压缩机的性 能。本文通过试验，进行对双螺杆制冷压缩机的多种冷却方式的研究，分析了中间喷液、尾部喷液以及油冷对于热 泵系统中制冷压缩机的排气温度、电机温度、压缩机性能及风冷热泵系统性能的影响。经过试验验证，对压缩机进 油进行冷却不仅可以降低压缩机排气温度和电机温度，提高压缩机的性能，而且对于系统的性能也有一定的改善； 尾部喷液对于压缩机的排气温度及电机温度降低非常有利，但在一定程度上降低了系统的性能；中间喷液方式，虽 然它降低了压缩机排气温度，提高了压缩机热力性能，但增加了电机的温度，降低了系统的性能。 关键词 双螺杆制冷压缩机；冷却方式；试验研究 Study on the Effect of Cooling MethOds on the Performance of Twin—Screw Refriger Ation Compressor in Heat Pump Wu Huagen，Xing Ziwen，Shu Pengcheng (School of Energy and Power Engineering，Xi’an Jiaotong University，Xi’an，China 710049) Abstract In the applications of the air—source heat pump。the semi—hermetic screw compressors are usually suf— fered with high discharge temperature and high temperature of electric motor．In order to solve those problems．three cooling methods are used which include oil cooling，injecting liquid refrigerant into compression chamber and injecting liquid refrigerant into suction line．In this paper，the effect of these cooling methods on the performance of semi—her— metic screw compressor is studied by the experiments．It is shown that the oil cooling is not only reducing the dis— charge temperature and the electric motor temperature，but also improve the compressor’s adiabatic efficiency and the COP of heat pump．Injecting liquid refrigerant into suction line can decrease the discharge temperature and electric mo— tor temperature much more than oil cooling．This method can also improve the compressor’s adiabatic efficiency．but the COP of heat pump wilI drop slightly．Injecting liquid refrigerant into compression chamber also can reduce the dis— charge temperature and improve the performance of compressor．But the electric motor temperature will increase and the heat pump’s COP becomes lower． Keywords Tw．n—screw refrigeration compressor；Cooling methods；Experimental study 近几十年来，风冷热泵系统因采用大气作为低 温热源，已经广泛应用于工业制冷以及家用中央空 调领域，因此得到了世界各国的普遍重视，也得到了 巨大的发展。双螺杆制冷压缩机也逐渐代替