PEMFC冷却剂循环条件下冷启动数值模拟

Numerical study on cold start of PEMFC with coolant circulation

质子交换膜燃料电池(PEMFC)具有高能量比、环境友好、工作温度低等优点,可用作未来新能源汽车的能量来源,具有很好的发展前景。然而零下温度启动时,电池内水结冰堵塞通道,严重影响电池启动性能及寿命。提出了PEMFC冷启动三维多物理场数值模型,考虑了冷却剂流动与传热的影响,对冷启动过程组分浓度、电势、温度、含冰量等参数进行了可视化分析。数值模拟结果与试验吻合良好,表明模型可用于预测电池冷启动性能并用于机理研究。

Proton exchange membrane fuel cells (PEMFC) show great potential to be considered as a renewable power system for future automobile applications due to their high power density and low operating temperature. However, a successful startup from subfreezing temperatures is a major challenge for the commercialization of PEMFC. In this research, a three-dimensional electrochemical-transport coupled model is developed. The model accounts the flow and heat transfer of the coolant during the cold start process. A detailed visualization analysis is conducted to illustrate the effects of a coolant system on the cold start performance. Our results include reactants concentration profiles, voltage curves, temperature distribution, and ice formation. The model validation results show good agreement between the model prediction and experimental data. Therefore, the model can be used to achieve a better understanding of PEMFCs cold start behavior.