Extended Application of the Moving Flame Front Model for Combustion of a Carbon Particle with a Finite-Rate Homogenous Reaction

摘要

The moving flame front (MFF) model with the assumption of an infinitely fast homogeneous reaction was successfully extended to use in the finite-rate cases, applying the concept of "'characteristic combustion rate of CO relative to its generation" and a universal "effectiveness-transforming formula". The predictions by the amended MFF model agree well with those by the rigid continuous-film model, no matter what kinetics of the homogeneous reaction are taken and no matter what the particle diameters are. In addition, the prediction of the particle ignition temperature is accurate too. Under certain conditions, the CO flame may yet appear in the boundary layer of a small carbon particle less than 100μm burning in air, which was confirmed by the Fourier transform infrared (FTIR) online measurement experiment and detailed modeling work using Sobolev's kinetics of CO oxidation directly measured at the flame front rather than in postflame regions.