Catalytic ignition of multi-fuels on platinum: Effect of strain rate

Numerical simulation of the catalytic ignition of multi-fuels is performed in a stagnation flow to identify the interaction among the primary components of gasified biomass on platinum surface. Simulations of selected single fuel are firstly performed and the results are compared with available experimental data. The results show that the ignition temperature increases with strain rates for the major biomass components as they are catalytically ignited individually. For H₂/CO mixture, the two components always ignite simultaneously and the existence of H₂ in the mixture will result in a lower ignition temperature than that for the sole CO. On the other hand, catalytic combustion of H₂ or CO would help to reduce the catalytic ignition temperature of CH₄ in the H₂/CH₄ or CO/CH₄ mixture. However, the ignition for the synthesized gasified biomass would depend on the fuel concentrations and the strain rate. The existence of other components in the simultaneous multi-fuels and the competitions between different fuels and oxygen for active surface sites change the catalytic ignition behavior. Higher strain rate would result in higher steady-state surface temperature, but it would also require higher ignition temperature. These phenomena can be explained by the characteristics of the surface coverage of the main surface species.