电除尘器绝缘子室数值模拟

发布时间：2018-06-30 06:54

本文选题：数值模拟 + 热风吹扫系统　；参考：《昆明理工大学》2017年硕士论文

【摘要】：近年来,空气污染十分严重,国家十分重视空气污染的治理。电除尘器作为一种重要的环保设备,在改善空气质量方面,发挥了十分重要的作用。由于烟气露点高、腐蚀性强,易在绝缘件表面结露,导致绝缘件经常性损坏,影响生产的正常进行,传统的做法是,在绝缘件周边安装电加热管,由于电加热管与绝缘件太近,热传导、热辐射使得瓷件上下温差过大,热膨胀产生的应力易使绝缘件炸裂,缩短了绝缘件的使用寿命,需要频繁地更换绝缘件,给工业生产造成严重的经济损失。为解决绝缘件频繁损坏的问题,本文针对采用热风吹扫系统的绝缘子室进行数值模拟,并且设置了 A、B、C三种方案。与方案A不同的是,方案B在承压绝缘子上盖板上开设了一定数量的小孔。方案C是为了探究通洞对绝缘子室内的温度场和速度场的影响而设的,首先,在SolidWorks中建立几何模型,然后将其导入到ICEMCFD中,对其进行网格划分及边界条件确定,接着运用ANSYS FLUENT对绝缘子室内的温度和速度分布情况进行数值计算,将计算结果导入到Tecplot 360进行处理,得到气流的温度场和速度场。通过方案A和方案B的对比分析可知,热风吹扫系统并不能使所有的振打部件内部及附近区域的温度高于露点温度,在靠近进口、出口附近区域的振打部件周围易出现温度低于露点的现象,可在这些部分增加实时地温度监测系统和电加热管,以此来维持高于露点的温度,避免绝缘件表面结露、腐蚀,另外,尽管承压绝缘子上盖板开孔使得热空气射流的射程变短、回流效果变差,导致更多的承压绝缘子和绝缘轴表面易受结露、腐蚀的威胁,但其使得承压绝缘子内外壁温差减小,同时使得进入电除尘器本体的热空气流速降低,降低了二次扬尘的可能性,通过方案A、B固定点的模拟温度与实测温度的比较可知,对于最不利温度区域,方案A、B的模拟结果与实测结果相一致。通过对方案C的数值模拟结果的分析可知,通孔的增大使得振打部件周围的温度场不能满足要求,极易在绝缘件表面结露。该课题的研究为解决绝缘件频繁破裂问题提供了新的思路,对于工业生产和环境保护,具有十分重要的意义。
[Abstract]:In recent years, air pollution is very serious, the state attaches great importance to the control of air pollution. As an important environmental protection equipment, ESP plays an important role in improving air quality. Because the smoke has high dew point, strong corrosiveness, easy to be exposed on the surface of insulating parts, which leads to frequent damage of insulating parts and affects the normal process of production, the traditional way is to install electric heating tubes around the insulation parts, because the electric heating pipes are too close to the insulating parts. The thermal conduction and radiation make the temperature difference between the top and the bottom of porcelain parts too big, and the stress produced by thermal expansion can easily crack the insulating parts and shorten the service life of the insulating parts. It is necessary to replace the insulating parts frequently and cause serious economic losses to the industrial production. In order to solve the problem of frequent insulation damage, the insulator chamber with hot air purging system is numerically simulated, and three kinds of schemes are set up. Different from scheme A, scheme B has a certain number of holes on the upper cover of the insulator. Scheme C is designed to explore the influence of the tunnel on the temperature field and velocity field in insulator room. Firstly, the geometric model is established in SolidWorks, and then it is imported into ICEMCFD for meshing and boundary condition determination. Then the temperature and velocity distribution in the insulator room are calculated by ANSYS fluent, and the results are introduced into Tecplot 360 to get the temperature field and velocity field of air flow. Through the comparative analysis of scheme A and scheme B, it can be seen that the hot air sweep system can not make the temperature of all the vibrating parts inside and around the dew-point temperature higher than that of the dew point, and it is near the inlet. The vibration components near the outlet are prone to appear the phenomenon of temperature lower than the dew point in the surrounding area. The real-time temperature monitoring system and electric heating pipe can be added to these parts to maintain the temperature higher than the dew point and to avoid the surface dew and corrosion of the insulating parts. In addition, although the opening of the upper cover of a pressurized insulator makes the range of the hot air jet shorter and the reflux effect worse, more pressurized insulators and insulating shaft surfaces are vulnerable to exposure and corrosion. However, it reduces the temperature difference between the inner and outer walls of the pressurized insulator, and at the same time reduces the flow velocity of the hot air entering the body of the electrostatic precipitator, thus reducing the possibility of the secondary hoisting dust. The comparison between the simulated temperature and the measured temperature at the fixed point of scheme Anb shows that, For the most unfavorable temperature region, the simulation results of scheme AHB are in agreement with the measured results. Through the analysis of the numerical simulation results of scheme C, it can be seen that the increase of the through hole makes the temperature field around the vibrating parts can not meet the requirements, so it is easy to be exposed on the surface of the insulating parts. The research of this subject provides a new way to solve the problem of frequent rupture of insulating parts and is of great significance for industrial production and environmental protection.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X701.2

【参考文献】