The Use of a High Temperature Wind Tunnel for MT-SOFC Testing - Part II: Use of Computational Fluid Dynamics Software in Order to Study Previous Measurements

摘要

Micro-tubular solid oxide fuel cells (MT-SOFCs) are a much smaller version of larger tubular SOFCs They are operational within seconds and allow a higher power density per volume than the larger version. Hence they are a potential technology for automotive, auxiliary and small scale power supply devices. In this study a commercially available computational fluid dynamic (CFD) software program was used to predict a MT-SOFCs performance when located inside a high temperature wind tunnel experimental apparatus. In Part I, experimentally measured temperature profiles were recorded via thermographic analyses and IIV curves. These measurements were used in this study to establish the predictability and validity of the CFD code and furthermore understand the MT-SOFC attributes measured in Part I, A maximum 4% IIV curve deviation and 6 K temperature deviation between the experimentally measured and model predicted results was observed. Thus, the model predicted the MT-SOFCs performance in the experimental environment very accurately. A very critical observation was the current density and temperature profile across the MT-SOFC that was strongly dependent on the distance from the hydrogenlfuel inlet. Not only was the model validated but also a grid and quantitative solution analysis is explicitly shown and discussed. This resulted in the optimum grid density and the indication that a normally undesirable high grid aspect ratio is acceptable for similar MT-SOFC modeling. These initial simulations and gridlsolution analysis are the prerequisite before performing a further study including multiple MT-SOFCs within a stack using different fuels is also envisaged.