Modeling The Pressure Drop And Thermal Profile Of A Novel Solid Oxide Fuel Cell Stack Design With A Homogenized Approach

Solid oxide fuel cells (SOFCs) represent a key technology in a scenario of decarbonisation of human activities for the next few years. Currently available stacks have high temperature gradients and large pressure drops across the stack, as well as uneven current distributions, contact loss and deterioration problems. An innovative stack design, dubbed "Chessboard", was devised at DTU Energy. The determination of the temperature, pressure and velocity fields in the stack by simulation is essential to evaluate the quality of a given design. In fact, it is not always possible to experimentally measure local physical quantities inside the stack. In this work a three-dimensional (3D) model of the stack has been constructed. L' modeling approach used is based on the homogenization technique. A computationally efficient method using simplified geometry, but with anisotropic thermophysical properties that mirror the true geometry of the stack to re-enhance the level of detail. Of all the physics describing phenomena in a SOFC, only fluid motion and heat transfer are actually solved by the model in the current stage of development, while electrochemical phenomena are defined as input parameters. Once the model was set up, a parametric study was performed, with the aim of obtaining the temperature and pressure profiles as a function of stack size, excess air, inlet air pressure and pore size . Thus identifying a safe operating window for the 4 parameters considered. The results show that it is possible to find different combinations of parameters that satisfy the design objective given by limits on the materials constituting the stack, all this with resolution times in the order of minutes.