化学链空气反应器数值模拟

Numerical Simulations on Air Reactor for Chemical Looping Process

空气反应器是化学链装置重要的反应器之一,空气反应器内的气固流动对化学链燃烧效率有重要影响,采用计算流体力学对带有内构件的空气反应器进行数值模拟,并研究了内构件厚度、数量和内构件之间的距离对气固流动的影响,内构件对颗粒浓度径向分布的改善采用标准差和径向非均匀指数评价.径向非均匀指数的变化趋势显示中等厚度的内构件作用范围较大,多个内构件的组合能够有效增大内构件的作用范围,适当增加内构件之间的距离有利于扩大内构件作用范围.

An air reactor is one of the important reactors for the chemical looping equipment,within which the gas-solid flow has a significant impact on the efficiency of chemical looping combustion.In this paper,computational fluid dynamics(CFD)simulations are performed on an air reactor with baffles.The influences of baffle thickness,the number of baffles,and the space between baffles on the gas-solid flow are studied,and the improvement effect of baffles on the radial solid distribution is evaluated by the standard deviation together with the radial non-uniformity index(RNI).The RNI profile shows that the medium baffle thickness and the combination of multiple baffles can effectively maintain a uniform radial solid distribution in the region away from the baffles.Moreover,an appropriate increase in the space between baffles also benefits the radial solid distribution.