上进风袋式除尘器内流场的数值模拟及优化研究

发布时间：2018-05-23 14:04

本文选题：上进风 + 袋式除尘器　；参考：《湖南大学》2015年硕士论文

【摘要】：目前,超细颗粒物是危害人体健康和污染大气环境的主要因素。随着国家对于超细颗粒物的控制越来越严格,作为一种对超细颗粒物具有高效去除效率的除尘设备,袋式除尘器将会有更加广阔的应用前景。本文基于FLUENT软件包对某公司实验平台的大型上进风袋式除尘器内流场进行了数值模拟及优化研究,主要内容包括四部分。首先,对上进风袋式除尘器内流场进行数值模拟研究,发现气流在袋室中分配不均匀,靠近进气室的滤袋容易破损,同时不同滤袋直径对袋式除尘器性能的影响需要进一步探究。第二,考察不同滤袋数目对上进风袋式除尘器内流场的影响。综合分析不同过滤速度下的流量分配系数、最大流量不均幅值、气流迹线、滤袋表面速度分布与压力损失等指标。结果表明:滤袋数为76个时,气流分布最为均匀,各滤袋负载均衡;相同过滤速度下,袋式除尘器的压降随滤袋数目的增加而上升,即压降大小顺序为9288847672;与72个滤袋相比,76个滤袋的可用过滤面积更大,综合考虑,袋式除尘器的最优滤袋数目为76个。第三,考察不同滤袋直径(Φ150和Φ130)对上进风袋式除尘器内流场的影响。综合分析滤袋流量分配系数、袋式除尘器箱体截面(Z=3300mm、5800mm)的速度和压力分布。结果发现,相比Φ150和Φ130两种滤袋混合布置,采用同一直径的滤袋后,袋室中各排滤袋的气流分配更加均衡,各横截面的速度和压力呈对称均匀分布。最后,对上进风袋式除尘器内部的气固相两相流动情况进行了模拟计算。通过分析T=0~5s的固体颗粒运动状态,以及T=5s时不同高度Z截面上的颗粒相浓度,结果表明:大部分颗粒从进气室进入袋室后,沿预先设置的缓冲区域向下运动,继而向排气口侧推进。上进风袋式除尘器能够很好的利用颗粒自重,降低袋式除尘器的压力损失,但同时不可避免的造成了靠近进气室一侧的滤袋颗粒负载较大,而靠近排气口一侧的滤袋负载的颗粒较少。模拟结果可以为上进风袋式除尘器的设计和优化提供依据。
[Abstract]:At present, ultrafine particulate matter is the main factor that endangers human health and pollutes the atmospheric environment. With the more and more strict control of ultrafine particles in our country, as a kind of dedusting equipment with high removal efficiency, bag dust collector will have a wider application prospect. In this paper, the numerical simulation and optimization of the flow field in a large upwind bag dust collector based on FLUENT software package are carried out. The main contents include four parts. First of all, the numerical simulation of the flow field in the upper inlet bag filter shows that the airflow is not evenly distributed in the bag chamber, and the filter bag near the inlet chamber is easy to be damaged. At the same time, the influence of different filter bag diameter on the performance of bag dust collector needs to be further explored. Secondly, the effect of different filter bag number on the flow field in the upper air bag filter is investigated. The distribution coefficient of flow, the uneven amplitude of maximum flow, the flow trace, the velocity distribution and pressure loss on the surface of filter bag were analyzed comprehensively. The results show that when the filter bag number is 76, the airflow distribution is the most uniform, and the load of each filter bag is balanced, and the pressure drop of the bag filter increases with the increase of the filter bag number at the same filtration speed. The order of pressure drop is 9288847672.Compared with 72 filter bags, the available filter area of 76 filter bags is larger. Considering comprehensively, the optimum filter bag number of bag filter is 76. Thirdly, the influence of different filter bag diameters (桅 150 and 桅 130) on the flow field in the upper air bag filter is investigated. The velocity and pressure distribution of the filter bag flow distribution coefficient and the cross section of the bag filter box are analyzed. The results show that, compared with 桅 150 and 桅 130, the airflow distribution of each filter bag in the bag chamber is more balanced, and the velocity and pressure of each cross section are symmetrical and uniform after adopting the same diameter filter bag. Finally, the gas-solid two-phase flow in the upper-inlet bag dust collector is simulated and calculated. By analyzing the motion state of solid particles in TX _ (0) O ~ (5) s and the particle phase concentration in Z section at different heights at T _ (5) s, the results show that most of the particles move downward along the pre-set buffer zone after entering the bag chamber from the inlet chamber. Then push to the side of the vent. The upper air bag filter can make good use of the particle weight and reduce the pressure loss of the bag filter, but at the same time, the filter bag particle load near the side of the inlet chamber is larger. But the filter bag near the side of the vent has less particles. The simulation results can provide the basis for the design and optimization of the upper inlet bag dust collector.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X701.2

【参考文献】