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In this paper, a preliminary control law, on the basis of the model-based analysis, is adopted to allow convenient integrations into a comprehensive power tracking control algorithm. The dynamic modeling methodology is employed to assess the dynamic responses of a SOFC stack under startup and load change conditions. The multi-disciplinary integration method is used to evaluate the stack characteristics. Effects of gas flow rates and differential temperatures between inlet flows and stack are investigated. In accordance with the stack specifications, the results will serve as a practical perception to minimize the heat input and shorten the startup time. While under load change conditions, proper air excess ratios are essential to stabilize the stack temperature profiles and to avoid the occurrence of abrupt temperature gradients in the stack.

This research is focused on the flow characteristics in channels and internal manifolds embedded on the interconnect of a planar solid oxide fuel cell (SOFC), by implementing both numerical simulations and optical experiments. The selected commercial computational fluid dynamics (CFD) code solves the three-dimensional fluid problems with a finite volume method, while laser Doppler velocimetry (LDV) is utilized to measure the two-dimensional flow field in the channels on a hydraulic half-model. It is shown that the trend of measured velocity distribution is quite consistent with the counterpart predicted by the concurrent simulation, which serves as the mutual benchmarking process for the both approaches. Furthermore, parametric studies are carried out numerically, to reveal the insights of flow characteristics in the flow passages. The results show that pressure balance mechanisms among various channels and in-/outlet plenums turn out to be a critical measure, as far as the velocity distribution is concerned.

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