Numerical Multiphase Flow Model to Study Channel Flow Dynamics of PEM Fuel Cell 2007-01-0696
We have studied the effects of water droplets presence in the PEM Fuel cell channel and the way they influence dynamics of the two-phase flow in the channel numerically. Dynamic behavior of a droplet on the surface of a channel has been modeled under the influence of surrounding fluid. Optimal conditions for the displacement of water droplet in the channel flow sought. For this purpose, the yield conditions for the displacement of liquid droplet on the surface of the channel under the influence of channel fluid are determined. The numerical solution is based on solving Navier-Stokes equations for Newtonian liquids. The study includes the effect of interfacial forces with constant surface tension, also effect of adhesion between the wall and droplet accounted by implementing contact angle at the wall. The Volume-Of-Fluid method is used to numerically determine the deformation of free surface. Water droplet and channel fluid properties, namely density and viscosity, inlet velocity, surface tension and channel geometry determine whether the droplet just deform and remain stationary or disintegrate from the surface. A comprehensive study is conducted, covering a wide range of viscosity ratio, density ratio, contact angle, droplet size and flow types. The border line between the disintegration region and equilibrium region is determined for different droplet surface tensions.