Effects of the Design and Optimization of Trapezoidal Channels and Baffles (Number and Position) on the Net Power Density of Proton-Exchange Membrane Fuel Cells

Abstract

The effects of the design and optimization of trapezoidal channels and baffles on the net power density of proton-exchange membrane fuel cells (PEMFCs) are studied. The significant effects of the length of upper and lower sides of the trapezoidal cross section and the number and position of baffles on the net power density of PEMFC have been investigated. It is found that at the same flow rate, changing the effective contact surface between the flow channel and the gas diffusion layer can tremendously improve the current density of fuel cells; moreover, the performance of a PEMFC based on the addition of a baffle can be further improved. The results show that the trapezoidal cross-sectional flow channel with baffles has higher efficiency and better overall performance compared with a basic straight flow channel. In addition, the response surface was used to optimize the trapezoidal cross-sectional flow channel by considering the power loss of output power and the flow rate. The optimal result was obtained with an upper side length of 1.234 mm, a lower side length of 1.8 mm, and a baffle from the entrance at 9.5 mm, increasing the net power density by 4.347%.