SOFC电流密度特性的ELCPI多尺度仿真

ELCPI Multiscale Simulation of SOFC Current Density Characteristics

对SOFC电化学反应扩散过程进行电流密度特性研究,有助于准确调控电流密度,提高电池运行安全性能以及延长电池寿命。分析电流密度的演变规律以及影响因素,往往无法有效仿真预测,只能粗略估测。为了准确快速地获取SOFC电流密度特性,提出了一种电化学反应扩散的投影积分多尺度方法(ELCPI)。建立SOFC电化学反应扩散的二维九速LB模型,对模型演化结果用二阶精度的Runge-Kutta法实施外推,实现对不同工况下SOFC电化学反应由开始至平衡这一过程的ELCPI仿真分析。结果表明,入口气体浓度、温度和压力是影响电流密度的主因,同时表明采用ELCPI能准确快速地获取电流密度特性。介观仿真结果为SOFC电流密度的运行控制提供了理论依据,有利于优化电池系统效率和保证SOFC运行安全。

The research on current density characteristics of SOFC electrochemical reaction diffusion process contributes to accurate current density control,improves operational safety performance and extends the life of the battery.At present,in the macroscale simulation,it can not be effective,while in the mesoscopic scale it can be roughly estimated,but no further analysis of the formation rule and influence factors of the current density characteristics is carried out.In order to quickly and accurately obtain the current density characteristics in SOFC,an EL CPI multiscale simulation method based on coarse projective integration about electrochemical reaction-diffusion was proposed in this paper.The two-dimensional lattice Boltzmann model of SOFC reaction-diffusion process was established.The obtained current density was extrapolated by Second-order Runge-Kutta method.The SOFC electrochemical reaction process from the start to the equilibrium was done with ELCPI multi-scale simulation under different work conditions.The results show that inlet gas concentration,temperature and work pressure have a significant effect on the current density.They also show that ELCPI can simulate the current density characteristics quickly and accurately.These mesoscopic simulation results of the SOFC current density provide a theoretical basis for the SOFC operation control,and contribute to the optimization of the efficiency of the battery system and ensure its safe operation.