Summary: | 碩士 === 國立臺灣大學 === 機械工程學研究所 === 93 === Recently the increasing energy price and the emission of greenhouse gases have become the major issues. A stack of fuel cells can produce electricity by converting hydrogen and oxygen into water, producing electricity in the process, which can be used to drive a motor to have a power work. The advantage of fuel cells is that they produce very little CO2, which causes global warming or nitrogen oxides that pollute the atmosphere. The PEMFC is one of them can convert hydrogen and oxygen into electric power without any pollution.
The study is to simulate the performance of PEMFC in different flow field and flow channel size by the software. The suitable of flow channel in PEMFC is one of the major concerning design parameters. The serpentine flow channel was popular in the design of traditional flow fields. However, the interdigitated flow channel is found to be a more efficient way in recent years. The effects of the concentration, pressure, velocity, temperature, and current density profiles on the flow fields will be studied in details. The serpentine flow field and interdigitated flow field are chosen for this study due to their different fluid transportation mechanisms. The serpentine flow channel drives the fluid to generate chemical reaction by diffusion; on the other hand, the reactant gases are forced from flow channel and into catalyst layer by interdigitated flow channel. The performance of the flow channel design will be evaluated by current-voltage (I-V) curves in the range of 0.3mm to 1.0mm for the channel depth and width.
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