超燃进气道激波/湍流边界层干扰

Studies of Turbulence/Shock Interaction in a Scramjet Inlet

关键词:  湍流  超声速边界层  激波/湍流干扰  进气道  大涡模拟 

Key words:  Turbulent flow  Supersonic boundary layer  Shock wave/turbulent interaction  Inlet  Large-eddy simulation

摘要:

针对超燃进气道湍流边界层/激波干扰引起的分离问题,采用基于5阶WENO数值格式的大涡模拟(LES)方法开展流场湍流非定常预测,旨在分析进气道湍流化技术实现进气道起动的可行性。研究表明,平板激波/湍流边界层干扰(STBLI)问题,LES方法能够清晰、可靠预测反射、分离激波形成过程及激波与充分发展湍流边界层的相互干扰,定量结果与试验一致；进气道研究方面,层流状态下,激波干扰产生强分离,导致进气道堵塞,而采用湍流化控制后试验和计算均表明流场分离明显减小,流场稳定且无明显堵塞现象,进气道可以起动,总压恢复系数达到要求,该结果表明,利用强湍流化减弱分离,实现进气道起动思想是可行的。 

Abstract:

Aiming at the separation induced by turbulent boundary/shock occurred in Scramjet inlet, a Large Eddy Simulation(LES)method based on the fifth-order weighted essentially nonoscillatory(WENO) scheme was adopted to predict the turbulent flowfield, providing assessment on the feasibility of the inlet turbulization to weaken separation for the inlet-start. The results indicate that the method of LES can simulate planar SWTBLI(shock wave/turbulent boundary layer interaction) well, manifesting the formation process of the reflection shock and the separation shock.The interference of the shock and turbulent boundary consistent with experimental data. Separation occurs at the inlet entrance under laminar flow and the inlet is blocked. However, the results of the experiment and numerical simulation adopting strong turbulization control show that the extent of the separated zone shrinks and the inlet starts steadily without blockage.The total pressure recovery coefficient is satisfactory, indicating the idea mentioned above is feasible. 