“研究生论坛”金属氢化物反应器的传热性能与反应特性分析

建立了内置螺旋换热管的金属氢化物反应器的三维数学模型，其特点是耦合了螺旋管内载热流体温度变化对反应过程的影响。根据所建模型并采用多物理场软件对反应器传热及反应过程进行数值模拟，分析了不同操作参数下反应器的传热性能与吸氢反应特性。结果表明：吸氢反应过程可划分为三个阶段，第一阶段主要受氢气压力影响，第三阶段主要受传热过程控制，其间为过渡段；氢气压力的减小能降低反应速率和床层平均温度，当其低至0.6MPa时，反应速率显著降低；载热流体温度的升高使传热温差减小，从而导致反应速率降低，当其高至323K时，反应已不能彻底进行；床层中，靠近螺旋管壁处温度较低，反应更为充分，但远离管壁的区域换热性能较差，反应较缓慢，由此指出了换热结构的改进方向。

Analysis of Heat Transfer Performance and Hydrogen Adsorption Reaction Characteristics of Metal Hydride Reactor

A three-dimensional mathematical model for the metal hydride reactor incorporating spiral coil tube was proposed. The specialty of the model was that it had coupled the effects of the variation of heat transfer fluid temperature on the hydrogen adsorption rate. The newly established model was solved using multi-physics software and the heat transfer performance and the hydrogen adsorption reaction characteristics under various operating conditions were investigated. The results showed that hydrogen adsorption reaction could be divided into three stages. In the first stage, hydrogen pressure was a major influence. In the third stage, the reaction was mainly under the control of the heat transfer process. And the second stage was a transition phase. As hydrogen pressure decreased, the reaction rate and the average bed temperature reduced. When the pressure decreased to 0.6MPa, the reaction rate reduced significantly. As the temperature of heat-transfer fluid increased, the temperature difference decreased, leading to reducing of reaction rate. When the temperature increased to 323K, the reaction was not complete and the reaction rate reduced remarkably. In the bed, the temperature in places near spiral coil tube was low and the reaction was completely finished. However, the heat transfer performance in places far away from spiral coil tube was relatively poor and the reaction was pretty slow. Therefore, there was a direction to improve the heat transfer structure.