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Showing 1 to 20 of 27 for “"boundary layer interactions"”.
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Unsteadiness in shock-wave/boundary layer interactions
… observed in shock<br/>wave/turbulent boundary layer interactions has been driving research in this area for<br/>several decades. This work investigates the interaction between an impinging oblique<br/>shock and a supersonic turbulent boundary layer via large-eddy simulations. …
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Atmospheric controls on soil moisture-boundary layer interactions
… state and the growth and development of the boundary layer (BL), leading to the triggering of convection. It is concluded that in mid-latitudes, for matters of convective triggering and response to land surface conditions, the critical portion of the atmospher~approximately1 to 3 km above the …
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Sidewall effects in compression corner shock-wave/boundary-layer interactions
… and research wind tunnels. When a shock wave boundary layer interaction (SBLI) occurs in a rectangular cross sectioned duct, the streamwise corner flows tend to separate, resulting in highly three-dimensional behaviour in the sidewall region. These corner separations have been seen to …
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Laminar/transitional shock-wave/boundary-layer interactions (SWBLIs) in hypersonic flows
Numerical investigations of laminar shock-wave/boundary-layer interactions (SWBLIs) in hypersonic flow have been carried out at M? = 6.85 and M? ? 8, with unit Reynolds numbers ranging from 2.0 x 106 m- l to 7.60 x 106 m- l. This thesis deals with a simplified 2-D geometric configuration to …
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Normal Shock Wave-Boundary Layer Interactions in Transonic Intakes at Incidence
… wave might appear and impinge on the incoming boundary layer. Flow separation may result from this interaction, leading to severe flow distortion. In order to maximise fuel efficiency by reducing aerodynamic drag, slimmer nacelle designs are currently being pursued by manufacturers. …
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Shock oscillation mechanisms of highly separated transitional shock-wave/boundary-layer interactions
… of the turbofan engine. Consequently, a laminar boundary layer persists on the suction side of the transonic fan during cruise. Additionally, the trend in compressor design is higher blade loading, leading to larger separations. These conditions combined induce a shock oscillation with …
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Modeling of shock boundary layer interactions and stability analysis using particle approaches
Hypersonic flow separation and laminar shock wave boundary layer interactions (SWBLIs) have received considerable attention since these interactions can lead to laminar to turbulent transition, unsteadiness, and localized high pressure and heating regions. Accurate predictions of these phenomena, …
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The effects of micro-vortex generators on normal shock wave/boundary layer interactions
Shock wave/boundary-layer interactions (SWBLIs) are complex flow phenomena that are important in the design and performance of internal supersonic and transonic flow fields such as engine inlets. This investigation was undertaken to study the effects of passive flow control devices on normal shock …
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Corner effects for oblique shock wave/turbulent boundary layer interactions in rectangular channels
… reflection is set to interact with the turbulent boundary layer (oblique SBLI) both on the bottom wall and in the corner formed by the intersection of the floor with the side-walls. In such a scenario, shock-induced separation is often seen in each of the streamwise corners, resulting in a highly …
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Numerical investigation of the wall temperature effects on shock-wave turbulent boundary layer interactions
The shock-wave turbulent boundary layer interaction (STBLI) is an important phenomenon in many practically relevant high-speed flow applications such as re-entry vehicles, air-breathing engines, rocket nozzles, etc. STBLI occurs in supersonic flow near solid surfaces where a shock wave is generated …
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Numerical Modelling of Shock Wave Boundary Layer Interactions in Aero-engine Intakes at Incidence
… shock wave. This produces undesirable shock wave boundary layer interactions (SWBLIs). Reynolds-Averaged Navier Stokes (RANS) turbulence models have been shown to be insensitive to the effects of boundary layer relaminarisation present in these highly-accelerated flows. Further, downstream of the …
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The effects of pressure waves on turbulent oblique shock wave boundary layer interactions in rectangular channels
Oblique Shock Wave--Boundary-Layer interactions (oblique SBLIs) occur in many practical applications, such as in mixed compression supersonic jet intakes and transonic compressor cascades and can have significant detrimental effects on the downstream boundary layer, resulting in flow distortion, …
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Design and development of a rectangular supersonic wind tunnel facility for the study of shock/boundary layer interactions
… simple, passive, and bleedless inlet shock wave/boundary layer interaction control options, called micro-vortex generators. A new supersonic wind tunnel was designed and built on the University of Illinois campus to enhance high-speed flow testing capabilities used for studying these flow-control …
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Experimental and numerical investigations of the off-design flow physics in a supersonic through-flow fan cascade
… to be strongly influenced. by upstream shock-boundary-layer-interactions, the strength of which varied with cascade incidence. In contrast, the peak levels of turbulence properties within the shear layer were found to be largely independent of cascade incidence, and could be characterized in …
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Quantification of Spalart-Allmaras Turbulence Modeling Uncertainties for Hypersonic Flows Utilizing Output-Based Grid Adaptation
… with complex flow features, such as shock wave-boundary-layer interactions (SBLI). The adapted meshes are generated using MIT Solution Adaptive Numerical Simulator (SANS) software, which is able to adapt high order unstructured meshes using a modified Continuous Galerkin (CG) finite element …
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Computational analysis of plasma actuation for control of shock-laden flows in scramjet isolators
… by instabilities associated with shock wave-boundary layer interactions (SWBLIs). These interactions can diminish engine performance and cause unstart, an aerodynamic phenomenon that can have catastrophic consequences. Plasma actuation has emerged as a promising approach to mitigate these …
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Heat Transfer and Flow Characteristics on the Rotor Tip and Endwall Platform Regions in a Transonic Turbine Cascade
… in regions with local flow reattachment and new-boundary layer formation. Conversely, the lowest heat transfer occurs in regions with boundary layer thickening and separation/lift-off flow. However, boundary layer separation results in additional secondary flow vortices, such as the squealer …
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Experimental and Numerical Investigations of Optimized High-Turning Supercritical Compressor Blades
… revealed the loss reduction mechanism: severe boundary layer separation occurred on the suction surface of the baseline blade while no separation occurred for the optimized blades. Furthermore, whether the boundary layer was separated or not was found due to different shock patterns, different …
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