基于文丘里喷嘴对滤芯反吹效果影响的数值模拟研究

Numerical Simulation Study on Influence of Venturi Nozzle on Back Blowing Effect of Filter Element

本文采用数值仿真的方法,模拟了气体经过文丘里喷嘴提速后对4 m长滤芯的反吹效果。分别研究了入口气速以及文丘里喷嘴的结构对滤芯反吹效果的影响。模拟结果为:反吹气体经过文丘里的提速,在喉管处的速度达到峰值,是入口速度的3.75倍。另外,在一定的范围内,喉管直径越小,反吹气在文丘里喉管处的峰值越大;喉管长度越短,反吹气体的喷吹范围越远;入口锥角越小,反吹气体的喷吹范围越远;出口卷边的半径越小,喷吹气体在一定的范围内速度衰减越慢;而入口处是否有直边、喉管段的长度对滤芯的喷吹性能影响不大。

In this paper,numerical simulation is used to simulate the back blowing effect of gas passing through a Venturi nozzle after increasing speed on a 4m long filter element.The effects of inlet gas velocity and the structure of the Venturi nozzle on the back blowing effect of the filter element are studied.The simulation result is that the velocity of the back blowing gas reaches its peak at the throat after passing through the Venturi,which is 3.75 times the inlet velocity.In addition,within a certain range,the smaller the diameter of the throat,the greater the peak value of back blowing at the Venturi throat.The shorter the length of the throat,the farther the blowing range of the back blowing gas.The smaller the inlet cone angle,the farther the blowing range of the back blowing gas.The smaller the radius of the outlet crimping,the slower the velocity attenuation of the blowing gas within a certain range.The presence of a straight edge at the inlet and the length of the throat section have little effect on the blowing performance of the filter element.