高超声速流场支杆射流减阻降热的流热耦合

Fluid-thermal coupling on drag and heat reduction induced by spike and jet in hypersonic flow field

为缓解高超声速飞行器头部面临的高温高压环境,针对支杆和逆向射流组合式减阻降热方案开展深入研究。基于有限体积法求解雷诺平均Navier-Stokes方程组,并采了切应力输运k-ω湍流模型模。采用共轭传热法求解固体热传导方程。结果表明:引入逆向射流将显著提高减阻降热性能。钝体头部阻力系数随着支杆长度增长显著降低,当支杆长径比从0.5增大至2.0时,阻力系数降低21%左右,而热流密度峰值几乎不受影响。提高逆向射流总压比能显著降低钝体头部壁面压力,但将逆向射流的附加阻力纳入考虑后,实际减阻效果反而变差。当逆向射流总压比从0.4升高至0.8时,钝体头部壁面热流密度峰值降幅达62.5%。通过共轭传热法分析表明,钝体头部结构温度随时间增长而显著上升,壁面热流密度峰值随着时间的推进而缓慢下降。

To alleviate the serious temperature and pressure environment of the forebody of hypersonic vehicle,the combined drag and heat reduction scheme of spike and opposing jet was studied in depth.The Reynolds averaged Navier-Stokes equations were solved based on the finite volume method,and the shear stress transport k-ωturbulence model was used.The conjugate heat transfer method was used to solve the heat conduction equation of solid domain.Results showed that the application of the opposing jet significantly improved the performance of drag and heat reduction.The drag coefficient of blunt forebody decreased significantly with the increase of spike length.With the length-to-diameter ratio of the spike increasing from 0.5 to 2.0,the drag coefficient decreased to about 21%.The peak value of heat flux was almost unaffected.Increasing the total opposing jet pressure ratio can significantly reduce pressure on the blunt forebody surface.Considering the additional drag induced by the opposing jet,as a result,the drag reduction effect became worse.With the total opposing jet pressure ratio increasing from 0.4 to 0.8,the peak value of heat flux on the blunt forebody surface decreased by 62.5%.The result of conjugate heat transfer analysis shows the temperature of blunt forebody increases significantly with time,and the peak value of heat flux decreases slowly with time.