CO与H₂氧化释热对煤油V型钝体稳焰器回流特性的影响

Aiming at the flow characteristics in the high-speed，low-oxygen afterburner combustion chamber，three chemical mechanisms with Large Eddy Simulation and Transport Probability Density Function（LES-TPDF）method were selected to calculate the two phase combustion flow field of a V-gutter flameholder with an inflow Mach number of 0.1. Results show that reversed-flow characteristics vary between different chemical mechanisms，making turbulent kinetic energy and recirculation zone length different. The analysis of heat release characteristics reveals that CO or H₂ are vigorously oxidized in bluff-body combustion. Too weak oxidation leads to low heat release rate at shear layer and weak mixing，hence a low turbulent kinetic energy and accumulating excess CO and H₂ in the recirculation zone，which reacts mildly and prolongs reversed-flow. The reaction exothermic is also analyzed in this paper and it is found that，for the Kundu mechanism，CO and H₂ oxidation exotherm only accounts for 25.30% of the overall process. While the skeleton mechanism and JL4 mechanism，with higher oxidation exotherm，account for 50.50% and 87.16%，which match experimental flow characteristics and are suitable for the study of the current condition.