操作参数对N阀流动行为影响的数值模拟

Numerical Study of the Effect of Operation Parameters on the Gas-solid Flow Characteristics in an N-type Loop-seal

运用计算颗粒动力学(Computation Particle Fluid Dynamics)Barracuda软件对一种低流动阻力的N型回料阀内的气固流动特征进行了数值模拟研究,研究了操作参数(充气量以及松动风比例等)的变化对其流动特征和返料特性的影响,并与U阀进行了对比。结果发现,随着总返料充气量的增加,N阀所能传递的颗粒返料率逐渐增加;保持总返料充气量不变,增加N阀松动风的比例,颗粒循环流率也逐渐增加,但相同条件下N阀的颗粒循环流率要明显大于U阀,说明N阀倾斜段的设计降低了回料阀的阻力,并减少了对松动风量的依赖。N阀的气体反窜明显低于U阀。

The gas-solid flow characteristics in a new type loop-seal （N loop-seal） with low flow resistance was mainly studied by Computation Particle Fluid Dynamics numerical meth- ods in this paper. The influence of operation parameters such as the aeration rate and the pro- portion of the loose-air to the gas-solid flow fields and the particle circulation rates were main- ly concerned. The results were compared between N loop-seal and the U loop-seal. The re- suits showed that the particle circulation rate increased with the total aeration rate and/or the proportion of the loose-air. N loop-seal had an advantage over the U loop-seal under the same condition. The improved slope structure of the supply chamber in N loop-seal reduced the flow resistance and the reliance to the loose-air rate. The gas inverse flow in N loop-seal is much less than that in U loop-seal.