【摘要】 为快速有效冲击破坏料仓出口上方形成的料拱,设计出一种能形成高速空气射流的收缩-扩张喷嘴。为探究喷嘴结构参数对空气射流速度的影响,采用正交试验与CFD数值模拟相结合的方法,优选出收缩段锥度60°、喉部直径2 mm、入口直径12 mm的喷嘴,并对其进行射流速度测试,测试结果与数值模拟结果的平均相对误差为4.8%。最后通过实验验证了空气射流冲击流化结拱粉体的有效性和快速性,并利用Fluent分析了射流冲击渗透粉体的区域,模拟结果与实验结果一致,揭示了空气射流与粉体颗粒相互作用的过程机制,为料仓破拱时合理布置射流喷嘴提供理论指导。更多还原

【Abstract】 In order to quickly and effectively destroy the powder arch formed above the outlet of the hopper, a convergent-divergent nozzle which could form a high speed air jet was designed. The influence of nozzle structure parameters on air jet velocity was analyzed by using CFD simulation and orthogonal test. The nozzle with conical degree of 60°, throat diameter of 2 mm and inlet diameter of 12 mm was selected. The test results are in good agreement with the numerical simulation results, and the average relative error is 4.8%. It is proved by experiments that the air jet can break the arch effectively and quickly. The jet penetration region simulated by Fluent is the same as experimental result. The process mechanism of air jet penetrating the powder is revealed, which can provide theoretical guidance for reasonable layout of jet nozzle to break arch.更多还原