错流板翅式换热器分布参数模型构建和优化研究

In this paper, a 3-D distributed parameter model of cross-flow plate fin heat exchanger(PFHE)is constructed using MATLAB program by considering the longitudinal and transverse heat conduction to study the flow and heat transfer of the multi-stream cross-flow PFHE. The simulation results coincide with the thermodynamic experimental results of the three-stream plate fin heat exchanger. An analysis is conducted on the effects of configuration and operation parameters of the cross-flow plate fin exchanger on heat transfer amount and the pump power. According to the results, the three-stream cross flow PFHE studied has an extreme value of pump power that shows the following changes: it first increases with the mass flowrate of fluid A, and when the mass flowrate reaches 1 300 kg/h, it decreases with the mass flowrate. Another analysis is carried out by setting four different xy projected areas of PFHE. The results are as follows: The amount of heat transfer basically remains the same when the xy projected area remains unchanged and the length of one side of the PFHE is changed; However, the amount of heat transfer per unit pump power is the greatest and the pump power consumption the lowest when the length of the PFHE along y direction is 0.15-0.20 m. The research findings provide theoretical guidance for the selection of optimized operation parameters, efficient and compact design of the cross-flow PFHE.