微型燃烧器内甲烷预混催化燃烧的数值研究

onsidering that micro combustion is easy to flameout, great heat loss, incomplete combustion and low efficiency and so on. The premixed catalytic combustion of methane in micro-combustor to improve combustion stability and combustion efficiency is studied. It lays the foundation for the technology of hydrocarbon-fuel combustion in micro-engine. Numerical Investigation of catalytic combustion, flow and heat transfer in micro-channels of three-dimensional micro-combustor was done by using laminar finite-rate and second-order upwind discretization model. The numerical Investigation results show that catalytic combustion efficiency increases while mass flow rate of methane decreases. While coefficient of excess air increases, catalytic combustion efficiency firstly increases and then decreases. Optimal coefficient of excess air increases, while temperature of catalytic wall increases and mass flow rate of methane decreases. Temperature of catalytic wall is the primary influence factor of catalytic combustion efficiency. Catalytic combustion efficiency increases immediately, while temperature of catalytic wall increases. To improve micro catalytic combustion efficiency, the optimal coefficient of excess air and a proper of oxygen-enriched (or fuel-rich) combustion method should be selected according as temperature of catalytic wall. While temperature of wall is treated as constant thermal boundary condition, catalytic combustion is mostly happened on the downside wall of combustion-chamber.