Simple numerical simulation of catalyst inks dispersion in proton exchange membrane fuel cell by the lattice Boltzmann method

Abstract

We used the lattice Boltzmann method (LBM) to simulate the dynamic behavior of catalyst particles during the ink dispersion process in a proton exchange membrane fuel cell. In the two-dimensional shear element, the single relaxation time lattice Boltzmann model, also called the lattice Bhatnagar-Gross-Krook model in the LBM, was used to simulate fluid flow, while the Lagrange model was used to simulate the motion of nanoparticles. The governing equation of particle motion includes fluid drag force, electrostatic repulsion, van der Waals force, ionomer force, and Brownian force. This model can be used to explore the effect of different shear strengths on the formation of agglomerates in inks. Our results showed that shear strength significantly influenced the formation and structure of agglomerates during the dispersion phase. Compared with a Reynolds number (Re) of 500 and 2000, a Re of 1000 achieved optimal dispersion and stability. When Re is 0, 500, 1000, and 2000, aggregate particles tend to form chain structure, packed structure, regular aggregate structure, and a large number of free particles and stacked particles, respectively.