硼基粉末燃料冲压发动机掺混燃烧特性研究OA北大核心CSTPCD

Aiming at the problem of combustion organization of boron-based powdered fuel ramjet,a gas-solid two-phase mixed combustion method was established.Numerical simulations were conducted under typical operating condition(26 km and Ma=6.0).The flow and combustion characteristics within the combustion chamber were obtained.And the effects of powder injection velocity,fuel particle size,and cavity structure on the gas-solid two-phase mixing combustion within the chamber was analyzed.The results reveals that the ignition temperature of powdered fuel is a key factor affecting the combustion efficiency of fuel blending.When pow-der is injected into the high-temperature zone of gas-phase combustion,the combustion efficiency can be significantly improved.A reasonable injection speed is beneficial for enhancing the mixing degree of particles,gas and incoming flow,making combustion more complete;When the particle size increases from 5 μm to 20 μm,the jet penetration depth significantly increases.The powder combustion efficiency is highest when the particle size is 5 μm.As the particle size increases,the difficulty of particle ignition in-creases,which is not conducive to sufficient combustion and heat release of the fuel;the recirculation zone formed by the concave cavity structure can create a better ignition area,which promotes the mixing of powdered fuel,rich combustion gas,and supersonic inflow,and improves combustion efficiency.