Effects of combustion parameters on reforming performance of a steam–methane reformer

•Effects of combustion parameters on the characteristics of a fuel cell reformer.•Fuel ratio and equivalence ratio as the combustion parameters.•Optimization of the production rates of H2 and CO can be achieved by adjusting the combustion parameters. The effects of combustion parameters on the reformer performance were studied in a 1-kW fuel cell reformer. A reformer system was numerically simulated using a simplified two-dimensional axisymmetric model domain with an appropriate user-defined function. The numerical results were compared with experimental data for validation. The fuel ratio, based on the flow rate of methane in the reforming reactor, was varied from 20% to 80%. The equivalence ratio was changed from ϕ=0.5 to 1.0. The results indicated that as the fuel ratio increased, the production rates of hydrogen and carbon monoxide increased, although their increase rate reduced. In fact, at the highest heat supply rates, the hydrogen production rate was actually slightly decreased. Simulations showed that the mixture had the highest fuel conversion rates and production rates of reformate gas at certain equivalence ratio and fuel ratio. This finding implies that adjusting the equivalence ratio and fuel ratio can significantly change the reformer characteristics and that the reforming performance can be optimized by adjusting them.