泵供液氨制冷装置管道阻力模拟及管径优化

Pressure drop simulation and pipe size optimization in ammonia pump feeding refrigeration system

建立泵供液氨制冷装置的吸气管和回汽管流动压降的数学模型。基于吸气管、回汽管流动压降模型和氨热力特性模型对泵供液制冷循环进行模拟分析。对制冷量为100 kW的某水产冷库制冰回路(152 m长回汽管和102 m长吸气管)的模拟计算结果表明:与传统的选径方法比较,通过程序优化选径可以使整个系统的COP上升7.6%;年节电达9092 kW·h;优化后管件尺寸增大而增加的初投资可在两年内回收。模拟计算结果也表明管径优化后的系统降低了压缩机的排气温度,间接延长了压缩机的使用寿命。

Mathematical models for pressure drop through both the compressor suction pipe and the evaporator returning pipe in ammonia pump feeding refrigeration system are developed.The system cycle's perforrnance parameters are simulated by aa computer program,which are developed based on both the pressure drop models and the thermal parameters models of the ammonia refrigerant.The program was used to simulate an ice making refrigeration loop with a capacity of 100 kW,a 102 m long compressor suction pipe and a 152 m long evaporator returning pipe.The simulation results show that,comparing to the traditional pipe selecting method,the pipe size optimized by the program is capable of increasing the system COP by 7.6%which corresponds to an annual energy saving of 9092 kW·h.The further analysis shows the cost caused by the optimization can be recalled within two years.The life period of refrigeration compressor can be extended because its discharged temperature reduced evidently after pipe size optimization.