Improving the Performance of an Air-Cooled Fuel Cell Stack by a Turbulence Inducing Grid

Air-cooled proton exchange membrane fuel cells ( ACPEMFC's) are gaining popularity as an alternative power source for their simplicity and quick startup. They're commercialized for large number of applications in the power range up to a few kWs. One of the problems regarding these fuel cells is the thermal management of the electrochemical reaction resulting in overheating of the air-cooled fuel cell stack (ACS) at low current densities, often around 0.4 Acm(-2). This study aims to solve the problem by placing turbulence grids before the cathode inlet. The purpose of the turbulence grids is to induce turbulences in the cathode channels and thereby induce a mixing effect and improve the heat transfer. A CFD model is build and assisted by experiments. The CFD results showed improvement of the mixing effect in the cathode channels and reduction of the channel wall temperature. The experiments resulted in 10.42% improved performance.