Lattice Boltzmann Simulation of Droplet Growth Processes in Flow Channel of Proton Exchange Membrane Fuel Cell

Liquid water transport is an important issue for water management in proton exchange membrane fuel cells (PEMFC). The lattice Boltzmann method (LBM) with multi-relaxation time (MRT) is presented to simulate the droplet growth process in the flow channel during the operation of PEMFC. The effects of different flow channel heights, contact angles of the flow channel surface, and the size, distribution and distance of liquid pores are considered. By analyzing the droplet shape changes and the detachment time, it is found that lower flow channel height and larger contact angle are favorable for droplet detachment, and the detached droplet mass is smaller. When two liquid pores are present, the droplet interaction hinders the droplet detachment, especially when the diameter of both pores is 35 μm, a liquid film is formed on the flow channel surface, and the droplet can be detached only by increasing the distance between the two pores.