Numerical methods of a 3D multiphysics,two-phase transport model of proton exchange membrane fuel cell(PEMFC)is studied in this paper.Due to the coexistence of multiphase regions,the standard finite element/finite volume method may fail to obtain a convergent nonlinear iteration for a two-phase transport model of PEMFC[49,50].By introducing Kirchhoff transformation technique and a combined finite element-upwind finite volume approach,we efficiently achieve a fast convergence and reasonable solutions for this multiphase,multiphysics PEMFC model.Numerical implementation is done by using a novel automated finite element/finite volume programgenerator(FEPG).By virtue of a high-level algorithmdescription language(script),component programming and human intelligence technologies,FEPG can quickly generate finite element/finite volume source code for PEMFC simulation.Thus,one can focus on the efficient algorithm research without being distracted by the tedious computer programming on finite element/finite volume methods.Numerical success confirms that FEPG is an efficient tool for both algorithm research and software development of a 3D,multiphysics PEMFC model with multicomponent and multiphase mechanism.
Two 1-D dynamical and isothermal models of cathode gas diffusion layer(GDL) with isobaric and non-isobaric operations for polymer electrolyte fuel cells(PEFCs) were developed and implemented in COMSOL Multiphysics v3.5.The artificial diffusion coefficient was introduced as well to make the numerical computation be stable.In the non-isobaric model,the pressure of gas mixture was obtained by summing up the governing equations of gaseous components,instead of Navier-Stoks equation.Comparison of the two models were carried out with the steady-states and dynamical simulations under given conditions.The corresponding analysis based on the simulated results was also given simultaneously.This paper is contributed to finding the differences between the isobaric and non-isobaric operation in the two-phase model of cathode GDL.
