利用计算流体动力学(CFD)方法,采用二维、可压缩、非稳态流动数学模型,对袋式除尘器脉冲喷吹过程中滤袋内的清灰流场进行了数值模拟,比较了滤袋壁面压力峰值的模拟值和试验值.同时,利用该模型,基于响应曲面法并使用统计软件MinitabV15研究了喷嘴直径、喷吹高度、文丘里管喉管直径、文丘里管及布袋长度对袋式除尘器清灰性能的影响,并得出了这5个影响因子的二次多项式预测模型.结果表明,滤袋表面压力峰值的模拟值与试验值变化趋势基本上是一致的,误差在10%左右,从而验证了本文数值计算模型的可靠性.在上述5个影响因素中,喷嘴直径(d)、文丘里管喉管直径(de)及布袋长度(L)对清灰性能影响显著,其中,清灰性能随着喷嘴直径和文丘里管喉管直径的增大而提高,随着布袋长度的增大先提高后降低.在本文所研究的尺寸范围内,当d=20mm、de=60mm及L=3360mm时,清灰效果分别达到最优.所得结论有助于进一步改善袋式除尘器的清灰性能.
The dust cleaning flow field in the filter bag during pulse-jet dust cleaning process was calculated by computational fluid dynamics (CFD) method,using a two-dimensional,compressible and unsteady flow mathematical model.The peak pressure on the bag wall of the simulated values and experimental values were compared.The effect of the nozzle diameter,jet height,throat diameter of the venturi tube,venturi tube and bag length on the dust cleaning performance were studied with this numerical calculation model,based on the response surface methodology (RSM) using the statistical software Minitab V15,and the quadratic polynomial prediction model of the above five impact factors was also developed.The results show that the simulated values of the pressure peak are basically the same as the experimental values with the error around 10%,which verifies the reliability of the calculation model.In the five impact factors,the nozzle diameter,throat diameter of the venturi tube and bag length have significant effects on the dust cleaning performance of the bag filter.The performance is improved with the increasing nozzle diameter and diameter of the venturi tube,and improved then degraded with the increasing bag length.Within the size range in this study,the dust cleaning effect is the optimal when d=20 mm,d e=60 mm,and L=3360 mm.The conclusions is useful in improving the cleaning performance of the bag filter.