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Experimental and numerical analysis of methanol steam reforming for fuel cell have been carried out. The reforming catalyst was supported by metal honeycomb to decrease the heat capacity. Conversion performances were improved by segmenting the catalyst into several blocks due to the enhancement of mixing of gases and heat transfer at the front edges of the segmenting catalyst. Numerical simulation model for methanol steam reforming catalyst was developed by changing chemical reactions in the model for exhaust catalyst of internal combustion engine and using a smaller mass transfer coefficient for methanol steam reforming. The calculated results for plate type methanol steam reformer which generates hydrogen of 7 kW (LHV) were also in good agreement with the measurements. It was found that the pattern of heat supply to catalyst and the reformer configuration affected the steam reforming performance. It was predicted that the optimized methanol steam reformer for 50 kW size fuel cell vehicle had a sufficient compactness.

A flow field survey and aerodynamic force measurements were carried out on a rotating circular cylinder, which was placed perpendicular to the flow near the transition Reynolds number. Remarkable changes in the unsteady wake flow pattern were observed to occur at a particular rotational Reynolds number, which is based on the peripheral speed of the cylinder, with a corresponding abrupt reduction in the steady lift force. The characteristics of the wake vortices also showed substantial difference below and above the same rotational Reynolds number. And it is also made clear that the upper limit of the periodic vortex formation was observed to be governed by a non-dimensional peripheral speed, which is the ratio of the rotational Reynolds number to the ordinary Reynolds number.