基于粒子成像测速法的正、负电晕放电下线-板式电除尘器内流场测试  

Measurements of Flow Field in Wire-plate Electrostatic Precipitator During Positive or Negative Corona Discharge Using PIV Method

作　　者：沈欣军[1,2] 曾宇翾[1] 郑钦臻[1] 闫克平[1] 

机构地区：[1]浙江大学生物质化工教育部重点实验室,杭州310027 [2]沈阳工业大学理学院,沈阳110870

出　　处：《高电压技术》2014年第9期2757-2763,共7页High Voltage Engineering

基　　金：国家高技术研究发展计划(863计划)(2013AAJY3111);浙江省公益技术应用研究项目(2010C31013)~~

摘　　要：电除尘器(ESPs)内流场的变化对细颗粒物的捕集具有显著影响。为此,采用粒子成像测速技术(PIV)测试了线–板式电除尘器模型内的流场。该电除尘器模型外壳为有机玻璃材质;放电极为2根不锈钢圆线且间距可调;示踪粒子为艾灸烟,一次流速约为0.5 m/s;流场测试平面垂直于收尘极和放电极的中心位置;分别施加正、负直流高压进行实验。结果表明,随着电压的增大,正、负电晕放电产生的离子风使得一次气流流速增大,最大增速分别可达0.6 m/s和0.7 m/s。当电压约为±30 kV时,2个放电极之间产生了4个涡旋;且电压越大,4个涡旋分布越均匀对称;较大的放电极间距更利于4个涡旋的形成。这些涡旋的存在会严重阻碍电除尘器内细颗粒物的捕集。In electrostatic precipitators （ESPs）, the variation of flow field greatly affects the capture of fine particles. Therefore, we measured the flow field in a wire-plate ESP model using particle image velocimetry （PIV）. The ESP model has side-walls made of acrylic, and two discharge electrodes made of two stainless-steel circle wires with adjustable spacing. We used moxa-moxibustion smoke as tracer particles, and the smoke＇s primary flow velocity was about 0.5 m/s. The observation plane of flow field was placed perpendicular to the central line between the discharge electrodes and the dust collecting electrodes. We applied either positive or negative DC high voltages in the experiments. The results show that the primary flow velocity increases with the applied voltage, and the maximum velocity increments reache 0.6 m/s and 0.7 m/s due to the ionic wind generated by the positive and negative corona discharge, respectively. When the applied voltage is about ：t：30 kV, there are four vortexes between the two discharge electrodes. The higher the applied voltage is, the more evenly and symmetrically the four vortexes distribute. Moreover, wider discharge electrodes spacing helps to generate the four vortexes. The vortexes seriously weaken the ESP model＇s capture efficiency of fine particles.

关 键 词：电除尘器 电晕放电 离子风 电流体流 流场 粒子成像测速法 示踪粒子 艾灸烟 

分 类 号：X701.2[环境科学与工程—环境工程]