Experiments on the Interaction with a Turbulent Boundary Layer of a Skewed Shock Wave of Variable Strength at Mach 2.5

Experiments on the Interaction with a Turbulent Boundary Layer of a Skewed Shock Wave of Variable Strength at Mach 2.5
Author: L. Michael Freeman
Publisher:
Total Pages: 26
Release: 1975
Genre: Aerodynamic load
ISBN:

This report covers an experimental study of the interaction of a skewed shock wave of variable strength with a turbulent boundary layer at a working Mach number of 2.5. The skewed shock wave was generated by a vertical wedge whose angle was varied in increments of 1 degree or less between 6 and 18 degrees in order to cover the spectrum of interaction from below incipient to widespread separation. Measurements include pressure distributions and oil flow photographs. The incipient separation angle was found to be between 71/2 and 8 degrees. For large wedge angles there is the appearance in the oil flow photographs of an inflection within the separated region, suggesting the possible approach to a secondary separation. The extent of separation is relatively small for angles up to 10 degrees, but grows more rapidly for larger angles. (Author).

Experiments on the Interaction with a Turbulent Boundary Layer of a Skewed Shock Wave of Variable Strength at Mach 2.5

Experiments on the Interaction with a Turbulent Boundary Layer of a Skewed Shock Wave of Variable Strength at Mach 2.5
Author: L. Michael Freeman
Publisher:
Total Pages: 32
Release: 1975
Genre: Aerodynamic load
ISBN:

This report covers an experimental study of the interaction of a skewed shock wave of variable strength with a turbulent boundary layer at a working Mach number of 2.5. The skewed shock wave was generated by a vertical wedge whose angle was varied in increments of 1 degree or less between 6 and 18 degrees in order to cover the spectrum of interaction from below incipient to widespread separation. Measurements include pressure distributions and oil flow photographs. The incipient separation angle was found to be between 71/2 and 8 degrees. For large wedge angles there is the appearance in the oil flow photographs of an inflection within the separated region, suggesting the possible approach to a secondary separation. The extent of separation is relatively small for angles up to 10 degrees, but grows more rapidly for larger angles. (Author).

Three-dimensional Shock Wave-turbulent Boundary Layer Interactions at Mach 6

Three-dimensional Shock Wave-turbulent Boundary Layer Interactions at Mach 6
Author: C. Herbert Law
Publisher:
Total Pages: 52
Release: 1975
Genre: Aerodynamic heating
ISBN:

Experimental results of an investigation of the three-dimensional interaction between a skewed shock wave and a turbulent boundary layer are presented. Surface pressure and heat transfer distributions and oil flow photographs were obtained at a freestream Mach number of 5.85 and two Reynolds numbers of ten and twenty million per foot. The model configuration consisted of a shock generator mounted perpendicularly to a flat plate. The shock generator leading edge was sharp and nonswept and intersected the flat plate surface about 8.5 inches downstream of the flat plate leading edge. The shock generator surface was 7.55 inches long and 3 inches high and its angle to the freestream flow was adjusted from 4 to 20 degrees. The generated shock waves were of sufficient strength to produce turbulent boundary layer separation on the flat plate surface.

Transition Location Effect on Shock Wave Boundary Layer Interaction

Transition Location Effect on Shock Wave Boundary Layer Interaction
Author: Piotr Doerffer
Publisher: Springer Nature
Total Pages: 540
Release: 2020-07-30
Genre: Technology & Engineering
ISBN: 3030474615

This book presents experimental and numerical findings on reducing shock-induced separation by applying transition upstream the shock wave. The purpose is to find out how close to the shock wave the transition should be located in order to obtain favorable turbulent boundary layer interaction. The book shares findings obtained using advanced flow measurement methods and concerning e.g. the transition location, boundary layer characteristics, and the detection of shock wave configurations. It includes a number of experimental case studies and CFD simulations that offer valuable insights into the flow structure. It covers RANS/URANS methods for the experimental test section design, as well as more advanced techniques, such as LES, hybrid methods and DNS for studying the transition and shock wave interaction in detail. The experimental and numerical investigations presented here were conducted by sixteen different partners in the context of the TFAST Project. The general focus is on determining if and how it is possible to improve flow performance in comparison to laminar interaction. The book mainly addresses academics and professionals whose work involves the aerodynamics of internal and external flows, as well as experimentalists working with compressible flows. It will also be of benefit for CFD developers and users, and for students of aviation and propulsion systems alike.

Shock Wave-Boundary-Layer Interactions

Shock Wave-Boundary-Layer Interactions
Author: Holger Babinsky
Publisher: Cambridge University Press
Total Pages: 481
Release: 2011-09-12
Genre: Technology & Engineering
ISBN: 1139498649

Shock wave-boundary-layer interaction (SBLI) is a fundamental phenomenon in gas dynamics that is observed in many practical situations, ranging from transonic aircraft wings to hypersonic vehicles and engines. SBLIs have the potential to pose serious problems in a flowfield; hence they often prove to be a critical - or even design limiting - issue for many aerospace applications. This is the first book devoted solely to a comprehensive, state-of-the-art explanation of this phenomenon. It includes a description of the basic fluid mechanics of SBLIs plus contributions from leading international experts who share their insight into their physics and the impact they have in practical flow situations. This book is for practitioners and graduate students in aerodynamics who wish to familiarize themselves with all aspects of SBLI flows. It is a valuable resource for specialists because it compiles experimental, computational and theoretical knowledge in one place.

Interaction of Two Glancing, Crossing Shock Waves with a Turbulent Boundary-Layer at Various Mach Numbers

Interaction of Two Glancing, Crossing Shock Waves with a Turbulent Boundary-Layer at Various Mach Numbers
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
Total Pages: 98
Release: 2018-07-08
Genre:
ISBN: 9781722499792

A preliminary experimental investigation was conducted to study two crossing, glancing shock waves of equal strengths, interacting with the boundary-layer developed on a supersonic wind tunnel wall. This study was performed at several Mach numbers between 2.5 and 4.0. The shock waves were created by fins (shock generators), spanning the tunnel test section, that were set at angles varying from 4 to 12 degrees. The data acquired are wall static pressure measurements, and qualitative information in the form of oil flow and schlieren visualizations. The principle aim is two-fold. First, a fundamental understanding of the physics underlying this flow phenomena is desired. Also, a comprehensive data set is needed for computational fluid dynamic code validation. Results indicate that for small shock generator angles, the boundary-layer remains attached throughout the flow field. However, with increasing shock strengths (increasing generator angles), boundary layer separation does occur and becomes progressively more severe as the generator angles are increased further. The location of the separation, which starts well downstream of the shock crossing point, moves upstream as shock strengths are increased. At the highest generator angles, the separation appears to begin coincident with the generator leading edges and engulfs most of the area between the generators. This phenomena occurs very near the 'unstart' limit for the generators. The wall pressures at the lower generator angles are nominally consistent with the flow geometries (i.e. shock patterns) although significantly affected by the boundary-layer upstream influence. As separation occurs, the wall pressures exhibit a gradient that is mainly axial in direction in the vicinity of the separation. At the limiting conditions the wall pressure gradients are primarily in the axial direction throughout. Hingst, Warren R. and Williams, Kevin E. Glenn Research Center...