液体火箭反推进再入过程底部热环境与流动特性OA

Reusable liquid-propellant launch vehicles constitute a pivotal direction for future space transportation sys-tems.During vertical re-entry of a rocket,the aft-mounted engines descend in an irregular configuration facing the freestream.The local thermal environment and flow characteristics are highly complex.A simulation study of the flow over a Falcon 9 v1.2 derived geometry was conducted for four representative re-entry phases:high-altitude powered deceleration,high-altitude aerodynamic deceleration,low-altitude aerodynamic deceleration,and low-altitude powered deceleration.The vehicle thermal environment is markedly transient and non-uniform:plume morphology evolves con-tinuously with altitude and engine operating condition.Powered deceleration phases exhibit substantially stronger flow disturbances and heat-flux maxima than aerodynamic deceleration phases owing to intense plume-freestream cou-pling.Secondary combustion exerts a global thermal influence on the far-field plume at low altitude.Across the four characteristic stages,the peak heat flux persistently localizes at the nozzle lip and the aft-edge of the rocket base,reaching 380 kW/m2,these data constitute a quantitative basis for engine thermal-protection design.