针对煤热解移动床反应器中需保证颗粒物料呈整体流流动状态的设计需求，采用离散单元法模拟了闭合型(圆形、三角形)和非闭合型(八字形)3种不同内构件设置对移动床内颗粒物料流动特性的影响. 结果表明，闭合型内构件设置下，当系统中形成稳定颗粒流动后，流动区宽度近似等于无内构件条件下流动区宽度与内构件在流动方向上最大投影尺寸的加和；非闭合型内构件设置下，根据内构件安放位置及翅片间距，可形成3种不同的流动结构，当翅片间距等于出口尺寸时，流动区宽度最大. 在所考察的参数范围内，存在最优的内构件安放位置(30d)和翅片间距(20d)(d为最大颗粒直径)，能使移动床出口处颗粒质量流率显著大于无内构件情况下的颗粒质量流率.
To satisfy the design requirement that in coal pyrolysis moving bed reactor the flow structure should be in mass flow pattern, the influences of insert settings on the flow behavior of granular assembly in moving bed were investigated by conducting discrete element simulations with three types of insert with different geometrical structures were considered: disk-shape, triangle-shape and splayed-shape. The simulation results showed that for disk-shape and triangle-shape inserts, the flowing zone width was approximately equal to the sum of the flowing zone width of the moving bed without insert and the maximum projection size of insert in the flowing direction. As to the splayed-shape insert, depending on its vertical position and the distance between the two wings there existed three types of flow structure. The flowing zone width achieved the maximum value when the distance between the two wings was equal to the outlet size. For the investigated conditions, there existed optimal vertical position(~30d) and the distance of wings (~20d) (d was diameter of the largest particle) under which condition the flow rate is notably larger than that for moving bed without insert.
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