关键词: 翅片管式蒸发器;仿真计算;低温室效应工质

Abstract: A distributed parameter mathematical model is set up for a finned tube evaporator under steady state, the actual flow condition is taken into consideration inside the evaporator in this model. Simulation program of the finned tube evaporator is written with VB language. Comparisons are also conducted between simulation results and data from experiment in the literature, the results show that the model has a good consistency. Based on this model, the characteristics of the flow and heat transfer of low global warming potential(GWP) working fluids R290, HFO1234yf and HFO1234ze in the finned tube evaporator are simulated. When the head-on wind speed, mass flow rate and pipe diameter size are altered, the change situation of heat exchange capacity and pressure drop are analyzed and the performance comparisons between the above low GWP refrigerants and the R410A which are now widely used are carried out. The results show that the R290 has the biggest heat exchange capacity and the HFO1234yf has the smallest under steady wind speed; HFO1234yf and HFO1234ze reach superheat state most easily in the same case. When the pressure drops are same, the mass flow rate of R410A is the maximum and the R290 is the minimum. When the heat exchange capacity is same, the mass flow rate of HFO1234yf is more than others and the R290 is smaller than the others. The model can provide theoretical basis for the optimization design and system matching of low GWP refrigerant finned tube evaporator and the refrigerant alternatives.

Key words: finned tube evaporator;simulation calculation;low global warming potential working fluid