Numerical Investigation of Heat/Flow Transfer and Thermal Stress in an Anode-Supported Planar SOFC

Abstract

To elucidate the thermofluid reacting environment and thermal stress inside a solid oxide fuel cell (SOFC), a three-dimensional SOFC model is implemented by using the finite element method in the commercial software COMSOL Multiphysics®, which contains both a geometric model of the full-cell structure and a mathematical model. The mathematical model describes heat and mass transfer, electrochemical reactions, internal reforming reactions, and mechanical behaviors that occur within the cell. A parameter study is performed focusing on the inlet fuel composition, where humidified hydrogen and methane syngas (the steam-to-carbon ratio is 3) as well as the local distribution of temperature, velocity, gas concentrations, and thermal stress are predicted and presented. The simulated results show that the fuel inlet composition has a significant effect on the temperature and gas concentration distributions. The high-temperature zone of the hydrogen-fueled SOFC is located at the central part of units 5, 6, and 7, and the maximum value is about 44 K higher than that of methane syngas-fueled SOFC. The methane-reforming and electrochemical reactions in the anode active layer result in a significant concentration gradient between the anode support layer and the active layer of the methane syngas-fueled SOFC. It is also found that the thermal stress distributions of different fuel inlet compositions are rather different. The maximum stress variation gradient between electrode layers of hydrogen SOFC is larger (44.2 MPa) than that of methanol syngas SOFC (14.1 MPa), but the remaining components have a more uniform stress distribution. In addition, the electrode layer of each fuel SOFC produces a significant stress gradient in the y-axis direction, and stress extremes appear in the corner regions where adjacent assembly components are in contact.

Numerical Simulation of Processes in an Electrochemical Cell Using COMSOL Multiphysics

“…To the best of our knowledge, there have been no similar models implemented in COMSOL Multiphysics according to the literature. However, there are similar models for methane fuel cells, such as the research conducted by Cai, W [5]. Nevertheless, in this study, a different fuel composition was considered, and the temperature regime, power, and configuration of the fuel cell also differed.…”

“…Symmetrical SOFCs enhance the harmony between cell parts and streamline the cell design. Anode-backed SOFCs can notably diminish resistive losses, leading to a decrease in the SOFC's operational temperature, and a more robust anode can facilitate internal reforming [5].…”

Numerical Modeling of Ammonia-Fueled Protonic-Ion Conducting Electrolyte-Supported Solid Oxide Fuel Cell (H-SOFC): A Brief Review

“…In line with the discussion, a few suggestions have been brought up in a few areas that should be taken into consideration in future modeling of the ammonia-fueled H-SOFC. Anode-supported flat tubular 3D model analysis [10] Thermal stress analysis on SOFC [65] Inlet fuel flow analysis in SOFC [66] COMSOL offers a wide range of benefits, including multiphysics simulation capabilities, a user-friendly interface, flexibility, and customization options. However, it also has limitations related to computational resources, learning curve, cost, model complexity, and post-processing challenges.…”

Numerical Study on Effects of Flow Channel Length on Solid Oxide Fuel Cell-Integrated System Performances

“…Through previous research, it is known that structural parameters are one of the important factors affecting SOFCs [6,7]. In order to analyze the influence of structural dimensions on the performance of SOFCs, numerous scholars have developed simulation models of SOFCs in various states [8][9][10]. Cui et al developed a two-dimensional model of a flat plate tube segmented tandem solid oxide fuel cell (FTS-SOFC) to analyze the impact of structural dimensions on the uniformity of cell voltage.…”