R32涡旋压缩机两相喷射制冷系统的设计与控制

R32涡旋压缩机存在排气温度过高的问题,利用两相制冷剂喷射可降低排气温度同时提升性能。基于经济器系统,提出了R32涡旋压缩机的两相喷射制冷系统,利用模拟仿真对其设计和控制方法进行了研究。从压缩机的角度,分析了喷射口等效直径对两相喷射压缩机性能的影响,并指出了两相喷射时喷射压力和喷射干度的优化方向。通过对两相喷射系统的模拟分析,在系统层面上对中间换热器的换热能力进行了优化配置和对中间喷射压力进行了优化控制,并提出根据排气温度来确定最优中间压力的方法,即将排气温度控制为135℃对应的中间压力为最优中间压力。经过优化后的两相喷射系统,不仅解决了排气温度过高的问题,而且能够提升制冷量7.1%~11.4%,提升COP 2.6%~6.2%。

Design and Control of R32 Two-phase Refrigerant Injection System Utilizing Scroll Compressor

To overcome the disadvantage of high discharge temperature in R32 compressor, two-phase refrigerant injection was proposed to decrease discharge temperature as well as improve system performance in severe conditions, and an improved injection system with economizer was proposed to realize two-phase injection. Based on the validated dynamic distributed parameter model of R32 scroll compressor, the optimization of heat transfer capability of internal heat exchanger and intermediate pressure according to system performance and discharge temperature were discussed. Through the optimized design and control of the two-phase injection system, the cooling capacity was enhanced by 7.1%-11.4% and COP was improved by 2.6%-6.2%.