Multiscale multiphase simulations at the gas channel/gas diffusion layer interface inside polymer electrolyte fuel cells

• A computational fluid dynamic model describing a straight channel, relevant for water removal inside a PEFC, is developed. A volume of fluid (VOF) approach is used to investigate the two-phase interface resolved flow behavior inside the gas channel including the gas diffusion layer (GDL) surface. The size and contact angle of the liquid inlet at the interface are calculated with the lattice Boltzmann approach. From our study, it is clear that the impact on the two-phase flow pattern for different hydrophobic/hydrophilic characteristics, i.e., contact angles, at the walls and at the GDL surface is significant, compared to a situation where the walls and the interface are neither hydrophobic nor hydrophilic, i.e., 90° contact angle at the walls and also at the GDL surface. A location at the side of the channel gives corner flow with a convex surface shape, while a location of the GDL surface liquid inlet in the middle of the gas channel gives droplet formation, having hydrophilic walls and a hydrophobic GDL surface.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Strömningsmekanik och akustik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Fluid Mechanics and Acoustics (hsv//eng)

Keyword

gas channel

gas diffusion layer

PEFC

volume of fluid

Publication and Content Type

kon (subject category)

ref (subject category)