SOFC多孔电极有效导热系数的实验和模型研究

Experimental and theoretical model study on effective thermal conductivity of SOFC porous electrode

固体氧化物燃料电池(SOFC)内部流动传热和化学反应复杂,容易产生热不平衡区。获取高精度的多孔电极有效导热系数对于建立多物理场耦合数值分析模型和电池热管理具有重要的意义。基于稳态法设计并搭建了多孔材料有效导热系统实验平台和测量系统,在372.1~932.4 K温度范围内详细测量了多孔电极实验样件温度分布,通过多孔材料内传热理论分析,基于现有EMT和ME1数学模型,利用比例因子t构造了温度修正的SOFC多孔电极综合有效导热系数的计算模型。同时通过对比孔隙率为0.2349~0.4178的3个实验样件表面温度的计算值和实验测量值,验证了该有效导热系数模型的有效性和高精度。

The flow heat transfer and chemical reaction inside the Solid Oxide Fuel Cell(SOFC)are complex,and it is easy to generate thermal imbalance zones.Obtaining high-precision effective thermal conductivity of porous electrodes is of great significance for the establishment of numerical analysis models of multi-physics field coupling and the thermal management.In this paper,an experimental platform and measurement system for the effective heat conduction system of porous materials was designed and constructed,which is based on the steady-state method.The temperature distribution of the porous electrode test specimens was measured in detail in the temperature range of 372.1~932.4 K.Through the theoretical analysis of heat transfer in porous materials,the calculation model of the comprehensive effective thermal conductivity of temperature-corrected SOFC porous electrodes was constructed using the scale factor t,which combines the existing EMT and ME1 mathematical models.In addition,the validity and high precision of the effective thermal conductivity model were verified by comparing the calculated values with the experimental measurements of the surface temperatures of the three test specimens with the porosity of 0.2349~0.4178.