Document Type : Full length

Authors

1 Hydrogen and Fuel cell Research Laboratory, Department of Chemical Engineering, Faculty of Engineering, University of Kashan, Kashan, Iran

2 Hydrogen and Fuel Cell Research Lab., Chemical Engineering Dep., Engineering Faculty, University of Kashan

Abstract

Micro-reformers used for producing hydrogen with a high surface-to-volume ratio in small-scale fuel cells were investigated. To this end, scrutinizing and exploiting all areas of micro reformers is very important. Parallel micro-channels have shown good performance in eliminating dead volumes. Inlet/outlet configuration has great effect on the velocity distribution through micro-channels. In this study, four configurations (1 inlet/1 outlet on the same and opposite sides; 1 inlet/2 outlets on the same and opposite sides) were studied through simulation and 1 inlet/2 outlets on opposite sides were found to have the lowest velocity difference, hence having the best configuration. Simulations were carried out at 600 °C, 1 atm, with S/C=3 and feed flow rate of 100 mL/min. Three channel patterns (i.e., parallel, splitting-jointing and pin-hole) were compared in terms of Figure of Merit (FoM) and specific conversion. Parallel channel design revealed a high value of specific conversion to be about 5.36×10−5 π‘˜π‘˜π‘˜π‘˜πΆπΆπΆπΆ4π‘šπ‘š2⁄, while splitting-jointing and pin-hole were 5.33×10−5 and 4.91×10−5, respectively. Based on FoM, pin-hole design had a high value of 1.34×10−5 π‘˜π‘˜π‘˜π‘˜πΆπΆπ» 4π‘šπ‘š2.𝑃𝑃𝑃𝑃⁄, while the values of splitting-jointing and parallel designs were 0.037×10−5 and 1.28×10−5, respectively.

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Main Subjects

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