FEM과 CFD 연동을 통한 스택 체결 시 압력에 의해 변형된 단위 전지 해석

초록

Polymer electrolyte membrane fuel cells (PEMFC) are currently being used in various transport applications such as drones, unmanned aerial vehicles, and automobiles. The power required is different according to the type of use, purpose, and the conditions adjusted using a cell stack. The fuel cell stack is compressed to reduce the size and prevent fuel leakage. The unit cells that make up the cell stack are subjected to compression by clamping force, which makes geometrical changes in the porous media and it impacts on cell performance. In this study, finite elements method (FEM) and computational fluid dynamics (CFD) analysis for the deformed unit cell considering the effects of clamping force is performed. First, structural analysis using the FEM technique over the deformed gas diffusion layer (GDL) considering compression is carried out, and the resulting porosity changed in the GDL is calculated. The PEMFC model is then verified by a three-dimensional, two-phase fuel cell simulation applying the physical properties and geometry obtained before and after compression. The detailed simulation results showed different concentration distributions of fuel between the original and deformed geometry, resulting in the difference in the distribution of current density is represented at compressed GDL region with low oxygen concentration.

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