Numerical Study on Collection Performance of Particulates in Hemispheric-Head Cyclone Separators for Fuel Cell Vehicles

Abstract

A hemispheric-head cyclone separator has higher collection performance of fine particles comparing with a conventional cyclone separator with a cylindrical head. In order to optimize the shape model with hemispheric-head, we have investigated numerically and experimentally the air flow in various shape cyclone models for industrials. The purpose of this study is to develop a cyclone model for fuel cell vehicles based on the results for industrials. Since this model is installed in a fuel cell vehicle, it must be compact due to space constraints. Therefore, as the first stage of development, based on a model of a dome-shaped cyclone separator with a cyclone diameter of 54 mm, we numerically investigated the airflow in the model by changing the dust holder size and the inlet pipe connection height. The motion of fine particles was analyzed considering only drag and gravity, and the effect of internal airflow on collection performance was investigated. As a result, it is shown that the model with the low inlet pipe connection height and the small volume of the dust holder has the highest collection efficiency. It was found that even if the entry particles in the dust holder return to the conical separator part due to small dust holder, the air flow field of the highest collection efficiency model has high centrifugal separation performance by lowering the connection height of inlet pipe. It is also the most suitable in terms of space for installation in fuel cell vehicles.