钝体逆向喷流减阻降温数值模拟

Numerical Investigation on Counter-flow Jets on Drag and Heat-transfer Reduction

采用基于SST湍流模型的N-S方程的CFD(computational fluid dynamics)数值模拟方法开展逆向喷流技术对超声速钝体减阻降温影响的研究。首先验证了文中采用的数值方法的可靠性,在此基础上对喷流质量流量变化及喷口尺寸变化对钝体产生的减阻降温效果的影响进行数值仿真及详细分析。计算结果显示:流场中可出现三种流动模态,即长射流穿透模态、振荡模态和短射流穿透模态;增大质量流量,阻力减小,热流减小;增大喷口直径,阻力减小,热流减小。文中的研究对钝体减阻降温技术在工程上的应用具有一定的参考价值。

N-S( Navier-Stokes) equations with SST turbulence model applied to to investigate the impact of counter-flow jet technology to supersonic blunt body for drag and heat reduction. At first, the numerical method applied in the paper is verified to be reliable, and on the premise, the affect of drag and heat reduction to the blunt body is numerically simulated and analyzed in detail based on change of jet mass flow and jet nozzle. The simulated result displays that there exist three flow modes in the mixing flow field. One is long penetration mode;the second is oscillation mode;the last is short penetration mode. The drag and heat on the blunt body with counter-flow jet is reduced through increasing mass flow and the same effect can also reach through enlarging the jet exit size. The results may be useful to some relative engineering application.