Fluid-thermal-structural coupled investigation on rudder leading edge with porous opposing jet in high-speed flow

High-speed air rudders face extreme force/thermal environments, and the opposing jet can improve the thermal environment in the stationary point and leading edge. In order to investigate the effect and mechanism of porous opposing jet on the rudder leading edge, the numerical study is carried out by using SST k-ω turbulence model and a loose fluid-thermal-structural coupled approach. The drag reduction and thermal protection mechanism of porous jet with different pressure ratios (PRs) is comprehensively compared and analyzed. The obtained results show that the fluid-thermal-structural coupled approach is necessary for the precise aerodynamic heat prediction of air rudder. The lowest temperature regions distribute in the upstream of orifices due to the jet cooling effect and heat conduction in the solid structure. The PR is an important factor influencing the interaction between jets. The porous opposing jet can provide a good effect in both drag reduction and thermal protection, as the maximum temperature drops to about 40 % from no jet to porous jet. As PR increases, the maximum pressure and temperature also decrease to a larger extent. However, the most PR should be a balanced consideration among the flowfiled, thermal structure and coolant consume.