Author: Kamalesh Kumar Sirkar
Publisher:
ISBN:
Category :
Languages : en
Pages : 130
Book Description
Convection Velocity of Turbulent Velocity Fluctuations Close to the Wall
Author: Kamalesh Kumar Sirkar
Publisher:
ISBN:
Category :
Languages : en
Pages : 130
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 130
Book Description
Wall-pressure Fluctuations and Pressure-velocity Correlations in a Turbulent Boundary Layer
Author: John S. Serafini
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 88
Book Description
This experimental study was carried out at a free-stream Mach number of 0.6 and a Reynolds number per foot of 3.45 x 106. The magnitudes of the wall-pressure fluctuations agree with the Lilley-Hodgson theoretical results. Space-time correlations of the wall-pressure fluctuations generally agree with Willmarth's results for longitudinal separation distances. The convection velocity of the fluctuations is found to increase with increasing separation distances, and its significance is explained. Measurements with the longitudinal component of the velocity fluctuations indicate that the contributions to the wall-pressure fluctuations are from two regions, an inner region near the wall and an outer region linked with the intermittency.
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 88
Book Description
This experimental study was carried out at a free-stream Mach number of 0.6 and a Reynolds number per foot of 3.45 x 106. The magnitudes of the wall-pressure fluctuations agree with the Lilley-Hodgson theoretical results. Space-time correlations of the wall-pressure fluctuations generally agree with Willmarth's results for longitudinal separation distances. The convection velocity of the fluctuations is found to increase with increasing separation distances, and its significance is explained. Measurements with the longitudinal component of the velocity fluctuations indicate that the contributions to the wall-pressure fluctuations are from two regions, an inner region near the wall and an outer region linked with the intermittency.
Pressure Fluctuations in Turbulent Boundary Layers
Author: M. V. Lowson
Publisher:
ISBN:
Category : Atmospheric pressure
Languages : en
Pages : 36
Book Description
Publisher:
ISBN:
Category : Atmospheric pressure
Languages : en
Pages : 36
Book Description
The Structure of Turbulent Shear Flow
Author: A. A. R. Townsend
Publisher: Cambridge University Press
ISBN: 9780521298193
Category : Mathematics
Languages : en
Pages : 450
Book Description
Develops a physical theory from the mass of experimental results, with revisions to reflect advances of recent years.
Publisher: Cambridge University Press
ISBN: 9780521298193
Category : Mathematics
Languages : en
Pages : 450
Book Description
Develops a physical theory from the mass of experimental results, with revisions to reflect advances of recent years.
A Study Phase Reversal of Turbulent Velocity Fluctuations Close to a Wall
Author: Kailung Kenneth Lau
Publisher:
ISBN:
Category :
Languages : en
Pages : 244
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 244
Book Description
Progress in Wall Turbulence 2
Author: Michel Stanislas
Publisher: Springer
ISBN: 3319203886
Category : Technology & Engineering
Languages : en
Pages : 430
Book Description
This is the proceedings of the ERCOFTAC Workshop on Progress in Wall Turbulence: Understanding and Modelling, that was held in Lille, France from June 18 to 20, 2014. The workshop brought together world specialists of near wall turbulence and stimulated exchanges between them around up-to-date theories, experiments, simulations and numerical models. This book contains a coherent collection of recent results on near wall turbulence including theory, new experiments, DNS and modeling with RANS, LES. The fact that both physical understanding and modeling by different approaches are addressed by the best specialists in a single workshop is original.
Publisher: Springer
ISBN: 3319203886
Category : Technology & Engineering
Languages : en
Pages : 430
Book Description
This is the proceedings of the ERCOFTAC Workshop on Progress in Wall Turbulence: Understanding and Modelling, that was held in Lille, France from June 18 to 20, 2014. The workshop brought together world specialists of near wall turbulence and stimulated exchanges between them around up-to-date theories, experiments, simulations and numerical models. This book contains a coherent collection of recent results on near wall turbulence including theory, new experiments, DNS and modeling with RANS, LES. The fact that both physical understanding and modeling by different approaches are addressed by the best specialists in a single workshop is original.
Turbulent Open Channel Flow, Sediment Erosion and Sediment Transport
Author: Clemens Chan-Braun
Publisher: KIT Scientific Publishing
ISBN: 3866449003
Category : Technology & Engineering
Languages : en
Pages : 190
Book Description
This thesis aims to contribute to a better understanding of turbulent open channel flow, sediment erosion and sediment transport. The thesis provides an analysis of high-fidelity data from direct numerical simulation of (i) open channel flow over an array of fixed spheres, (ii) open channel flow with mobile eroding spheres, (iii) open channel flow with sediment transport of many mobile spheres. An immersed boundary method is used to resolve the finite-size particles.
Publisher: KIT Scientific Publishing
ISBN: 3866449003
Category : Technology & Engineering
Languages : en
Pages : 190
Book Description
This thesis aims to contribute to a better understanding of turbulent open channel flow, sediment erosion and sediment transport. The thesis provides an analysis of high-fidelity data from direct numerical simulation of (i) open channel flow over an array of fixed spheres, (ii) open channel flow with mobile eroding spheres, (iii) open channel flow with sediment transport of many mobile spheres. An immersed boundary method is used to resolve the finite-size particles.
Surface Pressure Fluctuations Near an Axisymmetric Stagnation Point
Author: Richard D. Marshall
Publisher:
ISBN:
Category : Pressure
Languages : en
Pages : 76
Book Description
Surface pressure fluctuations on a circular disk placed normal to a turbulent air stream were investigated. Turbulence intensities of approximately 10% were produced by a coarse grid installed at the test-section entrance. The turbulent field in the neighborhood of the disk was homogeneous and nearly isotropic. Experimental results indicate that existing linear theories which do not consider distortion of the flow fail to predict the nature of surface pressure fluctuations on a bluff body. Only for wavelengths which are large compared to the body do these theories yield satisfactory results. A strong attenuation of the high frequency components occurs as the flow stagnates. This is accompanied by a transfer of energy from short to long wavelengths. The opposite effect is observed as the flow attains a radial direction and approaches the edge of the disk. A neutral wavelength which undergoes little change in energy was observed. Integral scales of surface pressure fluctuations are much larger than the lateral integral scale of the free-stream turbulence. (Author).
Publisher:
ISBN:
Category : Pressure
Languages : en
Pages : 76
Book Description
Surface pressure fluctuations on a circular disk placed normal to a turbulent air stream were investigated. Turbulence intensities of approximately 10% were produced by a coarse grid installed at the test-section entrance. The turbulent field in the neighborhood of the disk was homogeneous and nearly isotropic. Experimental results indicate that existing linear theories which do not consider distortion of the flow fail to predict the nature of surface pressure fluctuations on a bluff body. Only for wavelengths which are large compared to the body do these theories yield satisfactory results. A strong attenuation of the high frequency components occurs as the flow stagnates. This is accompanied by a transfer of energy from short to long wavelengths. The opposite effect is observed as the flow attains a radial direction and approaches the edge of the disk. A neutral wavelength which undergoes little change in energy was observed. Integral scales of surface pressure fluctuations are much larger than the lateral integral scale of the free-stream turbulence. (Author).
Turbulent Flows
Author: Jean Piquet
Publisher: Springer Science & Business Media
ISBN: 3662035596
Category : Technology & Engineering
Languages : en
Pages : 767
Book Description
obtained are still severely limited to low Reynolds numbers (about only one decade better than direct numerical simulations), and the interpretation of such calculations for complex, curved geometries is still unclear. It is evident that a lot of work (and a very significant increase in available computing power) is required before such methods can be adopted in daily's engineering practice. I hope to l"Cport on all these topics in a near future. The book is divided into six chapters, each· chapter in subchapters, sections and subsections. The first part is introduced by Chapter 1 which summarizes the equations of fluid mechanies, it is developed in C~apters 2 to 4 devoted to the construction of turbulence models. What has been called "engineering methods" is considered in Chapter 2 where the Reynolds averaged equations al"C established and the closure problem studied (§1-3). A first detailed study of homogeneous turbulent flows follows (§4). It includes a review of available experimental data and their modeling. The eddy viscosity concept is analyzed in §5 with the l"Csulting ~alar-transport equation models such as the famous K-e model. Reynolds stl"Css models (Chapter 4) require a preliminary consideration of two-point turbulence concepts which are developed in Chapter 3 devoted to homogeneous turbulence. We review the two-point moments of velocity fields and their spectral transforms (§ 1), their general dynamics (§2) with the particular case of homogeneous, isotropie turbulence (§3) whel"C the so-called Kolmogorov's assumptions are discussed at length.
Publisher: Springer Science & Business Media
ISBN: 3662035596
Category : Technology & Engineering
Languages : en
Pages : 767
Book Description
obtained are still severely limited to low Reynolds numbers (about only one decade better than direct numerical simulations), and the interpretation of such calculations for complex, curved geometries is still unclear. It is evident that a lot of work (and a very significant increase in available computing power) is required before such methods can be adopted in daily's engineering practice. I hope to l"Cport on all these topics in a near future. The book is divided into six chapters, each· chapter in subchapters, sections and subsections. The first part is introduced by Chapter 1 which summarizes the equations of fluid mechanies, it is developed in C~apters 2 to 4 devoted to the construction of turbulence models. What has been called "engineering methods" is considered in Chapter 2 where the Reynolds averaged equations al"C established and the closure problem studied (§1-3). A first detailed study of homogeneous turbulent flows follows (§4). It includes a review of available experimental data and their modeling. The eddy viscosity concept is analyzed in §5 with the l"Csulting ~alar-transport equation models such as the famous K-e model. Reynolds stl"Css models (Chapter 4) require a preliminary consideration of two-point turbulence concepts which are developed in Chapter 3 devoted to homogeneous turbulence. We review the two-point moments of velocity fields and their spectral transforms (§ 1), their general dynamics (§2) with the particular case of homogeneous, isotropie turbulence (§3) whel"C the so-called Kolmogorov's assumptions are discussed at length.
Measurements of the Correlation Between the Fluctuating Velocities and the Fluctuating Wall Pressure in a Thick Turbulent Boundary Layer
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description