Author: Jung-Hua Chou
Publisher:
ISBN:
Category : Compressibility
Languages : en
Pages : 258
Book Description
An Experimental Investigation of Compressible Turbulent Boundary Layers in an Adverse Pressure Gradient with and Without Surface Curvature
Author: Jung-Hua Chou
Publisher:
ISBN:
Category : Compressibility
Languages : en
Pages : 258
Book Description
Publisher:
ISBN:
Category : Compressibility
Languages : en
Pages : 258
Book Description
An Experimental Investigation of the Compressible Turbulent Boundary Layer with a Favorable Pressure Gradient
Author: David L. Brott
Publisher:
ISBN:
Category : Compressibility
Languages : en
Pages : 104
Book Description
The paper describes the results of a detailed experimental investigation of a two-dimensional turbulent boundary layer in a favorable pressure gradient where the free-stream Mach number varied from 3.8 to 4.6 and the ratio of wall to adiabatic-wall temperature has a nominal value of 0.82. Detailed profile measurements were made with pressure and temperature probes; skin friction was measured directly with a shear balance. The velocity- and temperature-profile results were compared with zero pressure gradient and incompressible results. The skin-friction data were correlated with momentum-thickness Reynolds number and pressure-gradient parameter. (Author).
Publisher:
ISBN:
Category : Compressibility
Languages : en
Pages : 104
Book Description
The paper describes the results of a detailed experimental investigation of a two-dimensional turbulent boundary layer in a favorable pressure gradient where the free-stream Mach number varied from 3.8 to 4.6 and the ratio of wall to adiabatic-wall temperature has a nominal value of 0.82. Detailed profile measurements were made with pressure and temperature probes; skin friction was measured directly with a shear balance. The velocity- and temperature-profile results were compared with zero pressure gradient and incompressible results. The skin-friction data were correlated with momentum-thickness Reynolds number and pressure-gradient parameter. (Author).
An Experimental Investigation of the Supersonic Turbulent Boundary Layer in a Moderate Adverse Pressure Gradient. Part II. Analysis of the Experimental Data
Author: W. B. Sturek
Publisher:
ISBN:
Category :
Languages : en
Pages : 58
Book Description
The experimental data reported in Part 1 are analyzed. Turbulent boundary layer equations applicable to compressible flow over a surface with longitudinal curvature are evaluated by numerical integration using the tabulated profile data. Curvature corrections to the equation for conservation of streamwise momentum are shown to be small but of the same order of magnitude as the wall shear stress. The data are shown to correlate in law of the wall and velocity defect dimensionless coordinates using an integral compressibility transformation. Values of skin friction coefficient calculated using the experimental data are compared to other experimental data and to values predicted using the Spalding-Chi method. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 58
Book Description
The experimental data reported in Part 1 are analyzed. Turbulent boundary layer equations applicable to compressible flow over a surface with longitudinal curvature are evaluated by numerical integration using the tabulated profile data. Curvature corrections to the equation for conservation of streamwise momentum are shown to be small but of the same order of magnitude as the wall shear stress. The data are shown to correlate in law of the wall and velocity defect dimensionless coordinates using an integral compressibility transformation. Values of skin friction coefficient calculated using the experimental data are compared to other experimental data and to values predicted using the Spalding-Chi method. (Author).
Method for Predicting Compressible Turbulent Boundary Layers in Adverse Pressure Gradients
Author: Shimer Zane Pinckney
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 68
Book Description
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 68
Book Description
Compressible Turbulent Boundary Layer Computations for Flow with Longitudinal Curvature
Author: Walter B. Sturek
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 32
Book Description
A numerical study has been performed using a finite-difference boundary layer computer program that includes corrections to the equations of motion for longitudinal curvature and allows the static pressure to be specified as a known function of x and y. Calculations with and without the corrections for longitudinal curvature and pressure gradient normal to be the local surface have been compared to experimental measurements of a supersonic turbulent boundary layer flow over a surface with concave longitudinal curvature. Substantially improved agreement with experimental measurements is obtained for the calculations including corrections for wall curvature and pressure gradient normal to the local surface for density profile, skin friction coefficient, and boundary-layer integral properties.
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 32
Book Description
A numerical study has been performed using a finite-difference boundary layer computer program that includes corrections to the equations of motion for longitudinal curvature and allows the static pressure to be specified as a known function of x and y. Calculations with and without the corrections for longitudinal curvature and pressure gradient normal to be the local surface have been compared to experimental measurements of a supersonic turbulent boundary layer flow over a surface with concave longitudinal curvature. Substantially improved agreement with experimental measurements is obtained for the calculations including corrections for wall curvature and pressure gradient normal to the local surface for density profile, skin friction coefficient, and boundary-layer integral properties.
Experimental Investigation of Compressible Boundary Layers Under the Influence of Pressure Gradients
Author: Raymond C. Wier
Publisher:
ISBN: 9781423574361
Category : Compressibility
Languages : en
Pages : 149
Book Description
This study examined the effect of mild pressure gradients on the mean and turbulent flow of high-speed boundary layers. Three Mach numbers (1.7, 3.0 and 5.0) were investigated. Three pressure gradients were examined; a zero pressure gradient (ZPG), a favorable pressure gradient (FPG), and a combined pressure gradient (CPG). The CPG consisted of an adverse pressure gradient followed by a favorable pressure gradient. Conventional pressure probes, hot- wire and particle image velocimetry (PIV) were used to examine the flow. Measurement included mean velocity, velocity turbulence intensity, mass flux turbulence intensity and energy spectra. Instantaneous (10 nsec) Mie scattering flow visualizations were acquired. Qualitatively, the flow visualizations indicated that the turbulent flow structures were strongly affected by the pressure gradients. For the Mach 2,8 case, the PIV contours and the hot-wire profiles both indicated that the boundary layer thickness increased by 40% and decreased by 100% relative to the ZPG for the favorable and adverse pressure gradients, respectively. Further, the PIV and hot-wire data indicated that the axial turbulence intensity levels increased by 22% for the CPG and decreased by 25% for the FPG. The energy spectra data indicated that once a pressure gradient was applied (favorable or adverse) the low frequency energy increased followed by a rapid decay. Lastly, it was found that nominally 20 to 30 PIV images were sufficient for mean flow boundary layer velocities, but 93 images (the maximum recorded in this study) were insufficient to adequately resolve Reynolds shear stresses.
Publisher:
ISBN: 9781423574361
Category : Compressibility
Languages : en
Pages : 149
Book Description
This study examined the effect of mild pressure gradients on the mean and turbulent flow of high-speed boundary layers. Three Mach numbers (1.7, 3.0 and 5.0) were investigated. Three pressure gradients were examined; a zero pressure gradient (ZPG), a favorable pressure gradient (FPG), and a combined pressure gradient (CPG). The CPG consisted of an adverse pressure gradient followed by a favorable pressure gradient. Conventional pressure probes, hot- wire and particle image velocimetry (PIV) were used to examine the flow. Measurement included mean velocity, velocity turbulence intensity, mass flux turbulence intensity and energy spectra. Instantaneous (10 nsec) Mie scattering flow visualizations were acquired. Qualitatively, the flow visualizations indicated that the turbulent flow structures were strongly affected by the pressure gradients. For the Mach 2,8 case, the PIV contours and the hot-wire profiles both indicated that the boundary layer thickness increased by 40% and decreased by 100% relative to the ZPG for the favorable and adverse pressure gradients, respectively. Further, the PIV and hot-wire data indicated that the axial turbulence intensity levels increased by 22% for the CPG and decreased by 25% for the FPG. The energy spectra data indicated that once a pressure gradient was applied (favorable or adverse) the low frequency energy increased followed by a rapid decay. Lastly, it was found that nominally 20 to 30 PIV images were sufficient for mean flow boundary layer velocities, but 93 images (the maximum recorded in this study) were insufficient to adequately resolve Reynolds shear stresses.
An Experimental Investigation of Turbulent Boundary Layers Along Curved Surfaces
Author: Ronald M. C. So
Publisher:
ISBN:
Category : Turbulent boundary layer
Languages : en
Pages : 276
Book Description
Publisher:
ISBN:
Category : Turbulent boundary layer
Languages : en
Pages : 276
Book Description
An Experimental Investigation of a Compressible Turbulent Boundary Layer Subjected to a Systematic Variation of Adverse Pressure Gradients
Author: Paul John Waltrup
Publisher:
ISBN:
Category :
Languages : en
Pages : 232
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 232
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 704
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 704
Book Description
Experimental Investigation of the Effect of a Systematically Varied Adverse Pressure Gradient on the Growth of Turbulent Boundary Layers
Author: Joseph Alfred Schetz
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description