Shock-wave/boundary-layer interactions (SBLI) are an important feature of high-speed gas dynamics. In many numerical studies of SBLI span-periodicity is assumed to reduce computational complexity. However, span-periodicity is not a valid assumption for aeronautical applications such as supersonic engine intakes where lateral confinement leads to highly three-dimensional behaviour. In this work transitional oblique SBLI are simulated for a rectangular duct with a $$\theta _{sg} = 5^{\circ }$$ θ sg = 5 ∘ shock generator ramp at Mach 2. The baseline configuration is a duct with an aspect ratio of 0.5. Time-dependent disturbances are added to the base laminar flow via wall localised blowing/suction strips to obtain intermittent transition upstream of the SBLI. Two forcing configurations are evaluated to assess the response of the SBLI to different tripping locations. The transition is observed to develop first in the low-momentum corners of the duct and spread out in a wedge shape. The central separation bubble is seen to react dynamically to oncoming turbulent spots, shifting laterally across the span. While instantaneous corner separations do occur, the time-averaged corner flow remains attached. Comparisons to a one-to-one aspect ratio duct show that the SBLI is heavily dependent on aspect ratio; the wider duct exhibited significantly larger regions of flow-reversal due to a strengthened interaction.

中文翻译：

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过渡矩形管道流中的冲击波/边界层相互作用

冲击波/边界层相互作用 (SBLI) 是高速气体动力学的一个重要特征。在 SBLI 跨度周期的许多数值研究中，假设可以降低计算复杂度。然而，跨度周期性不是航空应用的有效假设，例如超音速发动机进气口，其中横向限制导致高度三维行为。在这项工作中，过渡斜 SBLI 模拟了一个矩形管道，它具有 $$\theta _{sg} = 5^{\circ }$$ θ sg = 5 ∘ 2 马赫的激波发生器斜坡。基线配置是一个管道纵横比为 0.5。通过壁局部吹/吸带将时间相关的扰动添加到基础层流中，以获得 SBLI 上游的间歇性过渡。评估了两种强制配置以评估 SBLI 对不同跳闸位置的响应。观察到转变首先在管道的低动量角处发展，并以楔形展开。可以看到中央分离气泡对迎面而来的湍流点做出动态反应，在跨度上横向移动。虽然瞬时角分离确实发生，但时间平均角流仍然附着。与一对一纵横比管道的比较表明，SBLI 严重依赖纵横比；由于相互作用的加强，较宽的管道显示出明显更大的流动反转区域。可以看到中央分离气泡对迎面而来的湍流点做出动态反应，在跨度上横向移动。虽然确实发生了瞬时角分离，但时间平均角流仍然附着。与一对一纵横比管道的比较表明，SBLI 严重依赖纵横比；由于相互作用的加强，较宽的管道显示出明显更大的流动反转区域。可以看到中央分离气泡对迎面而来的湍流点做出动态反应，在跨度上横向移动。虽然确实发生了瞬时角分离，但时间平均角流仍然附着。与一对一纵横比管道的比较表明，SBLI 严重依赖纵横比；由于相互作用的加强，较宽的管道显示出明显更大的流动反转区域。