cfd simulation of methane steam micro-reformer: channel design and inlet/outlet configuration

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 𝑘g𝐶𝐻_4/𝑚^2 , 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 𝑘g𝐶𝐻_4/𝑚^2 pa, while the values of splitting-jointing and parallel designs were 0.037×10^−5 and 1.28×10^−5, respectively.