A New Formulation and an Efficient Numerical Technique for a Nonisothermal, Anisotropic, Two-Phase Transport Model of PEMFC

Abstract

In this paper, a new formulation and an efficient numerical technique are preliminarily studied for a nonisothermal, anisotropic, two-phase transport model of PEMFC, where flow, species, charge and energy equations are all addressed. The importance of water and temperature management are investigated in the anisotropic and nonisothermal point of view. Due to the employment of multi-phase mixture (M2) model, the diffusivity of water transport presents the significant discontinuity and degeneracy across the interface of single gas phase region and two-phase region. In addition, the distinct discontinuity of water diffusivity also emerges through the membrane. Such discontinuities and degeneracy of water diffusivity challenge the fast convergence of nonlinear iteration in numerical simulation, showing oscillating and even divergent iteration process. Based on an intensive new formulation of M2 model for PEMFC, an efficient numerical technique, Kirchhoff transformation, is specifically employed in order to overcome such numerical difficulties and achieve fast and convergent simulation. Numerical experiment is implemented accordingly to indicate the efficiency of the presented numerical technique, in contrast to the oscillating iterations without new numerical technique.