Computational Fluid Dynamics Simulation of Bio-Syngas Hetero-/Homogeneous Combustion over Platinum in Catalytic Micro-Combustors

Bio-syngas is a synthetic gas obtained from the thermal gasification of biomass. It contains carbon monoxide and hydrogen which is thought to be a cleaner fuel than biogas owing to its higher hydrogen content. In this work, the bio-syngas hetero-/homogeneous combustion over platinum in catalytic micro-combustors were studied through two-dimensional computational fluid dynamics model. Numerical simulations were carried out with a two-dimensional elliptic computational fluid dynamics code in conjunction with full-elliptic flow description, detailed hetero-/homogeneous chemistry, and all relevant heat transfer mechanisms in catalytic micro-combustors. In addition, we also studied the light-off of mixtures of carbon monoxide and hydrogen under lean conditions. The self-inhibition of carbon monoxide was found. Increasing carbon monoxide compositions result in an increase in the light-off temperature. Addition of hydrogen to the feed causes a reduction in light-off temperature for all compositions of carbon monoxide studied. The most significant shift in light-off temperature occurs with the addition of small amounts of hydrogen with only minor marginal enhancement occurring at higher hydrogen concentrations. Hydrogen alone in a lean atmosphere will oxidize at room temperature. Upon changing the activation energy between adsorbed hydrogen and oxygen, the carbon monoxide was observed to oxidize first, however, no enhancement of light-off was predicted