Assessment on hermetic property and mechanical compatibility of various groove-gasket sealing designs for solid oxide fuel cell stack

Abstract

Assessment among various groove-gasket designs under solid oxide fuel cell operating condition is presented. The gasket is deformable under the stress applied by external loading between 0.13-0.67 MPa. The operating temperature is from 30 to 800 °C. It has an indicated width of 1.95 mm and depth of 2.1 mm., which is accommodated in a square, triangular and U groove channel having the dimension of 2.0 × 2.0 mm 2. From the results, the U shape configuration provides the best performance with immeasurable leak rate under the applying load represented in term of global stress of 0.67 MPa. A stress analysis using Finite Element Method (FEM) tool, ABAQUS™, suggests sufficiently high compressive stress far exceeding the elastic limit with enough coverage of such high-stress area for U-shape design. In contrast, those from square and triangular designs posses relatively lower well-distributed stress and smaller region of highly concentrated stress, respectively. The associated deformed cross section suggests that the gasket has plastically deformed toward the U-shape wall surface at a greater degree than those for triangular-shape design. It can be concluded that the greater region in deformed gasket surface can more effectively reduce interconnectivity of micro channel on the interface between the gasket and the interconnector surfaces. © 2012 Elsevier B.V. All rights reserved.