Shock-Wave/Boundary-Layer Interactions in Transitional Rectangular Duct Flows

Abstract

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 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.

OpenSBLI: Automated code-generation for heterogeneous computing architectures applied to compressible fluid dynamics on structured grids

“…The code repository contains other applications that are not discussed in detail here, as they have been covered in previous work. These applications include supersonic laminar SBLI [57], laminar duct SBLI with sidewalls [9], transitional duct SBLI with sidewalls [8], and hypersonic roughness-induced transition at Mach 6 [58]. The numerical schemes in OpenSBLI have also been assessed and validated for supersonic Taylor-Green vortex cases [41], and supersonic turbulent channel flows [59].…”

“…It is capable of simulating complex wall-bounded flows with shockwaves, for supersonic and hypersonic CFD applications on curvilinear meshes. The purpose of this work is to describe the OpenSBLI software package and its use of codegeneration techniques, present a set of a validation and verification cases, and demonstrate a 3D shockwave boundary-layer interaction representative of ongoing research [8,9,10].…”

OpenSBLI: Automated code-generation for heterogeneous computing architectures applied to compressible fluid dynamics on structured grids

“…The code repository contains other applications that are not discussed in detail here, as they have been covered in previous work. These applications include supersonic laminar SBLI [50], laminar duct SBLI with sidewalls [51], transitional duct SBLI with sidewalls [52], and hypersonic roughness-induced transition at Mach 6 [53]. The numerical schemes in OpenSBLI have also been assessed and validated for supersonic Taylor-Green vortex cases [33], and supersonic turbulent channel flows [54].…”