金属氢化物吸附和脱附过程的数值分析

Numerical Simulation on the Processes of Adsorption and Desorption of Metal Hydride Material

结合化学吸附的机理，提出圆柱筒型金属氢化物吸氢、放氢的物理和数学模型．以金属氢化物ＬａＮｉ４．７Ａｌ０．３为例进行数值模拟，计算了不同时间的金属氢化物的反应锋面位置、热流量和吸氢量等参数．还研究了不同边界条件下，金属氢化物吸氢、放氢的传热传质情况及金属氢化物导热系数对金属氢化物的吸附、脱附的影响，并对不同类型金属氢化物在相同条件下的吸附性质进行了对比．研究证明：利用金属氢化物贮氢，应尽量减薄反应层的厚度；氢气的压力越高，吸附反应的速度越快；外界冷却水的温度对吸氢、放氢有明显影响；金属氢化物的导热系数越大，吸附反应的速度也越快．

By combining with the mechanism of chemical adsorption, a physical model and a mathematical model of a hydride in an annular cylinder were put forward to simulate the process of the hydrogen's storage and transmission. This paper fulfilled the numerical simulation on the adsorption processes of LaNi 4.7 Al 0.3 , and analysis of some parameters, such as the position of react front, heat flux, mass transfer, etc. The heat and mass transfer in the process of adsorption and desorption on different boundary conditions were discussed, and the effect of the metal hydride's thermal conductivity on hydrogen adsorption and desorption was studied. The analysis proves that a thinner layer of metal hydrides is beneficial for storing hydrogen. The higher the hydrogen pressures level while metal hydrides absorb hydrogen, the faster the reaction is. It is found that the outside cooling water temperature has a great effect on the rate of hydride and dehydride reaction, and the larger the thermal conductivity in metal hydrides, the higher the reaction speed.