A MATHEMATICAL-MODEL OF A TUBULAR SOLID OXIDE FUEL-CELL

The solid oxide fuel cell shows great potential as an efficient energy conversion system for use in central power stations. These cells can reform most hydrocarbon fuels with air to produce electricity and prov ide a heat source at 1000 degrees C while maintaining an efficiency of 60-75 percent. This paper describes a steady-state model for the pred iction of voltage, current, and power from a single-cell tube. The mod el is a distributed parameter electrical network that includes the eff ects of mass transfer resistance (concentration polarization), chemica l kinetic resistance (activation polarization), as well as relevant el ectrical resistances (ohmic losses). A finite-difference heat transfer model is also incorporated to allow for radial and axial temperature variations. The model computes the fuel and oxidant stream composition s as functions of axial length from energy and mass balances performed on each cell slice, The model yields results that compare favorably w ith the published experimental data from Westinghouse.