一种新型余热回收高温热泵机组的性能研究

Development and Experimental Validation of High Temperature Heat Pump for Heat Recovery

对一种新型的余热回收高温热泵机组进行了性能实验研究．机组主要由1台双螺杆制冷压缩机、1台冷凝器和蒸发器以及1个油冷却器组成．重点研究了喷油温度对高温热泵机组性能的影响，并拟合了排气温度随喷油温度变化的线性关系式．实验结果表明，这种新型的高温热泵机组能够达到稳定的出水温度85℃，可以在较宽的高温工况范围内运行，性能系数较高．研究表明，喷油温度和喷油量的选取是改进高温热泵机组性能的主要方法；在冷凝温度高于70℃运行时，最佳的油冷却温度应控制在45～65℃之间，机组能效比最大可提高6．3％．

The performance of a high temperature heat pump unit for heat recovery is experimentally evaluated. The unit consists of a twin-screw refrigeration compressor, a condenser, an evaporator and oil cooler. The effect of the oil cooling on performance of the heat pump unit is theoretically analyzed. The effect of the oil injection temperature on performance is also evaluated. The discharge temperature linearly changes with the temperature of oil injection. Results show that the unit enables to stably get an outlet water with temperature 85 ℃ and works in a wide range of high temperature conditions with high coefficient of performance, and the keys to improving the high temperature heat pump unit often lie on the selection of oil cooling temperature and oil quantity. The best oil cooling temperature should be controlled between 45 ℃ and 65 ℃ when the condensing temperature is above 70 ℃, and the oil cooling can increase the heat capacity of the heat pump by 6.3 %.