摘要
为了改善袋式除尘器脉冲清灰性能,基于航空航天等领域拉瓦尔喷管技术,设计了适用于脉冲喷吹袋式除尘器的新型喷嘴——拉瓦尔型喷嘴,运用CFD仿真技术结合实验研究,分析喷吹压力和喉部直径对喷嘴清灰性能的影响,并与相同孔径常规喷嘴对滤袋的响应和清灰效率进行对比分析。结果表明:采用拉瓦尔型喷嘴进行清灰时,滤袋侧壁正压力峰值是常规喷嘴的1. 29倍;拉瓦尔型喷嘴对长袋的清灰效果更为明显,一次喷吹清灰效率可达96%,证明该拉瓦尔型喷嘴在袋式除尘领域具有较好的应用前景。
A new nozzle Laval nozzle applicable to pulse-jet bag filter was designed based on the Laval nozzle technology in aerospace field for improving the pulse cleaning performance of bag filter. By use of CFD simulation technology and in combination with experimental study,this paper analysed the influence of injection pressure and throat diameter on cleaning performance,and conducted comparative analysis on response and dust cleaning efficiency of common nozzles with the same bore diameter. The results showed: when Laval nozzle was used for dust cleaning,it had the positive pressure peak value of bag sidewall 1. 29 times more than that of common nozzles; and Laval nozzle had a more significant dust cleaning effect on long bags,with one-time dust cleaning efficiency up to 96%. Therefore,Laval nozzle had a better application prospect in bag filter field.
引文
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