新型金属氢化物反应床传热性能分析

Performance Analysis of Heat and Mass Transfer on a Metal Hydride Reactor

运用计算流体动力学(CFD)方法,对弓形折流板壳管式金属氢化物反应床进行了数值模拟.预测了反应床壳侧的流体流动状态,分析了在不同折流板数量下,反应床中壳侧的流动状态、壳侧压降和换热管内合金的温度分布.分析计算结果发现,当壳侧折流板数较多时,热流介质的流动均匀性较好,其流动死区较少,换热性能较好,壳侧压降也较大,压降损失主要存在于折流板圆缺处;增加折流板高度会有效地减少壳侧压降,并对换热性能影响很少.针对弓形折流板壳管式反应床传热性能较差,引入螺旋式折流板对反应床进行优化.结果表明,该反应床流体流动状态为旋转式,其壳侧流体的均匀性、壳侧压降以及换热管的温度分布均匀性均明显优于弓形折流板.

In the metal hydride compression cycle, the heat and mass transfer performance of the reactor has great impact on the system efficiency. A computational fluid dynamics （CFD） method was used to sim- ulate the performance of heat and mass transfer on a new reactor bed with segmental baffle plate. The sim- ulation on the reactor bed with different numbers of baffles and research on the unsteady state of the bed under a particular baffle number were carried on. As a result, the flow performance of reactor increases and heat transfer properties of reactor change less with the baffle number. Hence, the baffle of spiral-plate type is indicated to optimize the above reactor. The simulation process proves that the new type reactor shows better heat and mass transfer performances than the reactor with segmental baffles.