ABSTRACT

Electrostatic precipitators (ESP) are used extensively for removing particulates from a gas flow by charging the particles and then removing them in the presence of an electric field. Traditional ESP designs use the walls of the flow channel as the grounded collection surface. The objective of this present study is to evaluate a novel ESP configuration, recently patented by Ohio University’s Electrostatic Laboratory, in which an array of vertical surfaces of cylindrical geometry are placed in a crossflow configuration and used as grounded collection surfaces. A numerical approach was adopted by developing and implementing User-Defined Functions (UDFs) in ANSYS Fluent computational fluid dynamics (CFD) software to build a two-dimensional cross-flow ESP model, for the first time, for the gas flow and particulate capture. The two-dimensional numerical models proved useful in shedding light on the basics of the collection process in the novel cross-flow ESP. In the studied configuration, the collection of the particles on the collector surface was limited to the anterior and posterior surfaces of the first and second collection rows, respectively. The collection at the posterior surface of the second row presented interesting behavior, with the particles becoming entrained in the wake of the collectors and the electric field from the discharge electrode located downstream that was opposite to the fluid flow direction. The output of the simulation underestimated the experimental data. The lower efficiency prediction of the model could have been due to the vibration of the collection electrodes, collection by the mist formed in the wet system, and particle agglomeration in the experiments. The results of this study provide critical information in improving the particulate efficiency of novel cross-flow ESP and other similar cross-flow ESP systems.

Implications: A novel Electrostatic precipitator (ESP) configuration (recently patented) was evaluated. A numerical approach was adopted to build a cross-flow ESP model, for the first time, for the gas flow and particulate capture. The collection of the particles on the collector surface was limited to the anterior and posterior surfaces of the first and second collection rows. Also, the particles were entrained in the wake of the collectors. The output of the simulation underestimated the experimental data. The results of this study provide critical information in improving the particulate efficiency of novel cross-flow ESP and other similar cross-flow systems.

摘要

静电除尘器 (ESP) 广泛用于通过为颗粒充电然后在存在电场的情况下去除它们来从气流中去除颗粒。传统的 ESP 设计使用流道壁作为接地收集表面。本研究的目的是评估一种新型 ESP 配置，该配置最近获得了俄亥俄大学静电实验室的专利，其中一系列圆柱形几何形状的垂直表面被放置在交叉流配置中并用作接地收集表面。通过在 ANSYS Fluent 计算流体动力学 (CFD) 软件中开发和实施用户定义函数 (UDF)，采用数值方法建立二维错流 ESP 模型，首次用于气流和颗粒捕获. 二维数值模型证明有助于阐明新型错流 ESP 中收集过程的基础知识。在研究的配置中，收集器表面上的颗粒收集分别限于第一和第二收集行的前表面和后表面。第二行后表面的收集​​物呈现出有趣的行为，粒子随着收集器和来自与流体流动方向相反的下游放电电极的电场而被夹带。模拟的输出低估了实验数据。该模型的较低效率预测可能是由于收集电极的振动，湿系统中形成的雾气收集，和实验中的颗粒团聚。本研究的结果为提高新型错流 ESP 和其他类似错流 ESP 系统的颗粒效率提供了关键信息。

影响：评估了一种新型静电除尘器 (ESP) 配置（最近获得了专利）。首次采用数值方法建立了气流和颗粒捕获的错流 ESP 模型。收集器表面上颗粒的收集仅限于第一和第二收集行的前表面和后表面。此外，颗粒被收集器带走。模拟的输出低估了实验数据。这项研究的结果为提高新型错流 ESP 和其他类似错流系统的颗粒效率提供了关键信息。