Investigation in the Effect of Gravity on the Droplet Removal in the Flow Channel of PEMFC

Abstract

Dealing with a droplet on the flow channel of PEMFC, a mathematical model based on the force balance of the flow force, gravity and hysteresis tension is derived to address the expressions of the critical airflow velocity and the droplet radii. The results show that in the horizontal flow channel, the critical airflow velocity is hardly affected by the working temperature but decreasing with the increasing of operation pressure. The droplet removal capability can be enhance by increasing the tilt angle of the cell. For a small droplet, the operation pressure has an apparent effect on the airflow velocity, while for a droplet in the spontaneous departure area, this effect can be neglected.