熔融碳酸盐燃料电池的计算流体力学模拟

Computational fluid dynamics numerical simulation of molten carbonate fuel cells

为研究熔融碳酸盐燃料电池内发生的传热传质和电化学反应等物理化学过程,建立了一个三维数学模型.模型综合考虑了电池内的流体流动、传热、多组分传递、电化学反应及电压-电流关系等.利用计算流体动力学(CFD)技术对数学模型进行了数值模拟计算,得到了不同流动形式(顺流、逆流和叉流)电池内的温度和组分的体积分数等的详细的空间分布,分析和讨论了相应的传递机理.结果表明阴极的出口温度大于阳极,且逆流方式有利于降低出口温度;化学反应速度主要取决于阳极燃料气体的体积分数.

A three-dimensional model was developed to simulate the physical and chemical processes （heat and mass transfer, electrochemical reaction, etc. ） that occurred in molten carbonate fuel cells. The mathe- matical model simultaneously accounts for the fluid flow, heat transfer, multicomponent transport, electrochemical kinetics and voltage-current relations. The model was numerically solved using computational fluid dynamics technique to simulate molten carbonate fuel cell with different flow fields （cross-, co-, and counter-flow fields）. The spatial distributions of temperature and component concentrations were obtained in detail, and the transport mechanism was described and discussed. It is found that temperature at cathode outlet is higher than the value at anode outlet for different flow fields that the value for co-flow fields is lower than the value for the other two fields; and that the reaction speed is determined by fuel concentration at the anode.