R32制冷系统在变吸气状态下的热力性能

Thermodynamic performance of R32 refrigeration system under variable suction conditions

压缩机的吸气状态对系统的性能有重要影响,通过理论与实验的方法,探究不同吸气条件下系统性能的变化,以寻找实现系统最佳运行时的吸气状态。基于小型水冷冷水机组实验系统,调节电子膨胀阀的开度来控制制冷剂在系统内的流量,进而通过实验探究吸气状态对制冷系统性能的影响。结果表明:在吸气状态从过热到气液两相的过程中,系统的制冷量会先增加后减少。与此同时,压缩机的功耗会先略微上升,随后缓慢下降。排气温度的变化则表现为两段式的降低,特别是在吸气达到两相状态时,温降更为明显。吸气干度在0.98—1.00时,可以实现系统的制冷量和系统性能系数C_(OP)的最优,能显著提高制冷系统的整体性能和经济效益。这些发现对于解决恶劣工况下压缩机润滑油碳化问题以及优化制冷系统具有重要意义。

The suction state of the compressor significantly influences the system′s performance.Through theoretical and experimental methods,the aim is to explore the variations in system performance under different suction conditions,seeking to identify the suction state that achieves the optimal operation of the system.Utilizing a small-scale water-cooled chiller experimental system,the flow of refrigerant in the system was controlled by adjusting the opening of the electronic expansion valve,thereby experimentally investigating the influence of the suction state on the performance of the refrigeration system.The results indicate that during the transition of the suction state from superheated to a two-phase gas-liquid state,the refrigeration capacity of the system initially increases and then decreases.Simultaneously,the power consumption of the compressor slightly rises initially,followed by a gradual decline.The change in discharge temperature shows a two-stage reduction,especially when the suction reaches the two-phase state,with a more pronounced cooling effect.When the vapor quality at suction is between 0.98 and 1.00,the system achieves optimal refrigeration capacity and coefficient of performance C OP,significantly enhancing the overall performance and economic benefits of the refrigeration system.These findings are of paramount importance for addressing compressor lubricating oil carbonization issues under harsh operating conditions and optimizing refrigeration systems.