Gas dynamics in channels of a gas-feed direct methanol fuel cell: exact solutions

The gas dynamics in channels on both sides of a gas-feed direct methanol fu el cell (DFMC) are considered. The basic equations for the flow velocity an d density are derived, taking into account the mass and momentum transfer t hrough the channel/backing layer interface. For the practical case of small inlet velocities the analog of the Bernoulli equation is formulated and th e exact solution of nonlinear gas dynamics equations is obtained. It is sho wn that the flow in both the cathode and anode channels is incompressible ( its density is constant) and electrochemical reactions affect only the flow velocity v. Simple formulae for v, as a function of local current density and effective water drag coefficient are derived. (C) 2001 Elsevier Science B.V. All rights reserved.