标题： 稀薄环境中的横向湍流射流 显示英文标题

标题： Lateral turbulent jet in rarefied environment

摘要： 侧向射流在控制高超音速飞行器的轨迹和气动加热方面起着关键作用。然而，湍流和稀薄效应之间的复杂相互作用很少被研究。本研究通过采用新开发的GSIS-SST方法[J. Fluid Mech. 1002 (2025) A10]，该方法结合了用于湍流的剪切应力传输（SST）模型和用于稀薄气体流动的一般合成迭代方案（GSIS），填补了这一知识空白。发现，在50公里到80公里的高度范围内，GSIS-SST与纯GSIS（SST）之间的俯仰力矩最大相对差异达到28%（20%）。虽然射流旨在降低表面热流，但其湍流显著削弱了这种降低效果，例如，当射流压力比为1.5时，GSIS-SST预测的热流比GSIS高一个数量级。增加攻角会增强局部湍流，导致GSIS-SST与GSIS之间剪切应力和热流的差异扩大。这些见解加深了我们对侧向射流流动的理解，并强调了在中高度高超音速飞行中考虑湍流和稀薄效应的重要性。 显示英文摘要

摘要： Lateral jets play a crucial role in controlling the trajectory and aerodynamic heating of hypersonic vehicles. However, the complex interaction between turbulent and rarefaction effects has rarely been examined. This study fills this knowledge gap by employing the newly developed GSIS-SST method [J. Fluid Mech. 1002 (2025) A10], which combines the shear stress transport (SST) model for turbulent flow and the general synthetic iterative scheme (GSIS) for rarefied gas flow. It is found that, at altitudes from 50 km to 80 km, the maximum relative difference in the pitch moment between the GSIS-SST and pure GSIS (SST) reaches 28% (20%). While the jet is supposed to reduce the surface heat flux, its turbulence significantly diminishes this reduction, e.g., the GSIS-SST predicts a heat flux about one order of magnitude higher than the GSIS when the jet pressure ratio is 1.5. Increasing the angle of attack intensifies local turbulence, resulting in expanded discrepancies in shear stress and heat flux between GSIS-SST and GSIS. These insights enhance our comprehension of lateral jet flows and highlight the importance of accounting for both turbulent and rarefaction effects in medium-altitude hypersonic flight.