Dusty-Gas Model Conservation Law and Approximate Analytical Solutions for H2-H2O Transport in the SOFC Anode Support Layer

A complete Dusty-Gas Model for the H$_2$--H$_2$O mixture in the anode transport layer of the anode-supported SOFC is considered. An exact conservation law relating the total pressure and the hydrogen molar fraction at any point in the anode to their values in the anode channel is derived. Using this conservation law, approximate analytical solutions for the hydrogen molar fraction and total pressure in the anode transport layer are obtained. The solutions can be used to calculate the concentration overpotential.