关键词: 燃料电池, 风机系统, 供气模式, 速度分布, 换热性能

Abstract:  In this article, based on the self-made air-cooled proton exchange membrane fuel cell, a simulation model of the cathode fan system is presented, and then it is validated for the accuracy of the model by experiments. With the model built, the influence on the air flow and temperature distribution with three air feeding modes, like blowing mode, suction mode and diversion mode, for fan system is studied. As a result, it shows that the air flow distribution uniformity of cathode outlet is poor when it works in the blowing mode, the reason for this is the boundary layer separation at the outlet of the fan, and the separated low-speed gas flow forms a backflow in the hub, which affects the distribution uniformity of the downstream gas flow; both suction mode and diversion mode can effectively improve the uniformity of the cathode air flow distribution of the stack and enhance the local heat transfer performance of the stack. At the fan speed of 25 000 r/min, the maximum temperature difference of the stack operating in the blowing mode, suction mode and diversion mode is 7.9 ℃, 5.4 ℃ and 6.5 ℃, respectively, it illustrates that the temperature distribution of the stack operating in the suction mode is more uniform.