Effect of Reynolds Number on the Large Structure of Turbulent Boundary Layers PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Effect of Reynolds Number on the Large Structure of Turbulent Boundary Layers PDF full book. Access full book title Effect of Reynolds Number on the Large Structure of Turbulent Boundary Layers by R. W. Smith. Download full books in PDF and EPUB format.
Author: R. W. Smith
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: R. W. Smith
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Alexander J. Smits
Publisher:
ISBN:
Category : Reynolds number
Languages : en
Pages : 50
Get Book Here
Book Description
Author: James G.. Brasseur
Publisher:
ISBN:
Category : Reynolds number
Languages : en
Pages : 30
Get Book Here
Book Description
Author: Randall William Smith
Publisher:
ISBN:
Category :
Languages : en
Pages : 712
Get Book Here
Book Description
Author: Ramis Örlü
Publisher: Springer
ISBN: 9783319862866
Category : Technology & Engineering
Languages : en
Pages : 250
Get Book Here
Book Description
This volume collects the edited and reviewed contribution presented in the 7th iTi Conference in Bertinoro, covering fundamental and applied aspects in turbulence. In the spirit of the iTi conference, the volume is produced after the conference so that the authors had the opportunity to incorporate comments and discussions raised during the meeting. In the present book, the contributions have been structured according to the topics: I Theory II Wall bounded flows III Pipe flow IV Modelling V Experiments VII Miscellaneous topics
Author: Peter W. Runstadler
Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 326
Get Book Here
Book Description
A combination of visual and quantitative measurements is presented, providing a physical picture of the turbulent boundary layer flow structure on a flat plate. The flow structure is shown to consist of three zones, each zone has a one to one correspondence to the well known regions of the u+, y+ mean velocity profile. A wall layer region is shown to exist below y+ = 10. An apparently fully turbulent region exists corresponding to the logarithmic ''law of the wall'' and the ''buffer'' region. An intermittent zone appears to agree closely with the ''wake'' deviation region. An entirely new result of the investigation is the delineation of the structure of the wall layer region. This region is shown to contain a relatively regular structure of low and high velocity fluid streaks alternating in the span direction, together with the ejection of low momentum fluid into the outer flow. Correlations are given for the rate of ejection and the streak spacing. A qualitative description of other features of the wall layer region and the character of the remainder of the boundary layer flow structure is presented. (Author).
Author: A. A. R. Townsend
Publisher: Cambridge University Press
ISBN: 9780521298193
Category : Mathematics
Languages : en
Pages : 450
Get Book Here
Book Description
Develops a physical theory from the mass of experimental results, with revisions to reflect advances of recent years.
Author: Nathan R. Tichenor
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
High-speed high Reynolds number boundary layer flows with mechanical non-equilibrium effects have numerous practical applications; examples include access-to-space ascent, re-entry and descent, and military hypersonic systems. However, many of the basic turbulent flow processes in this regime are poorly understood and are beyond the realm of modern direct numerical simulations Previous studies have shown that curvature driven pressure gradients significantly alter the state of the turbulence in high-speed boundary layers; the turbulence levels have been shown to decrease by large amounts (up to 100 percent) and the Reynolds shear stress has been shown to change sign. However, most of our understanding is based on point measurement techniques such as hot-wire and Laser Doppler anemometry acquired at low to moderate supersonic Mach numbers (i.e., M = 2-3). After reviewing the available literature, the following scientific questions remain unanswered pertaining to the effect of favorable pressure gradients: (1) How is state of the mean flow and turbulence statistics altered? (2) How is the structure of wall turbulence; break-up, stretch or a combination? (3) How are the Reynolds stress component production mechanisms altered? (4) What is the effect of Mach number on the above processes? To answer these questions and to enhance the current database, an experimental analysis was performed to provide high fidelity documentation of the mean and turbulent flow properties using two-dimensional particle image velocimetry (PIV) along with flow visualizations of a high speed (M4.88=), high Reynolds number (Re[is almost equal to]36,000) supersonic turbulent boundary layer with curvature-driven favorable pressure gradients (a nominally zero, a weak, and a strong favorable pressure gradient). From these data, detailed turbulence analyses were performed including calculating classical mean flow and turbulence statistics, examining turbulent stress production, and performing quadrant decomposition of the Reynolds stress for each pressure gradient case. It was shown that the effect of curvature-driven favorable pressure gradients on the turbulent structure of a supersonic boundary layer was significant. For the strong pressure gradient model, the turbulent shear stress changed sign throughout the entire boundary layer; a phenomena was not observed to this magnitude in previous studies. Additionally, significant changes were seen in the turbulent structure of the boundary layer. It is believed that hairpin vortices organized within the boundary layer are stretched and then broken up over the favorable pressure gradient. Energy from these hairpin structures is transferred to smaller turbulent eddies as well as back into the mean flow creating a fuller mean velocity profile. It was determined that the effects of favorable pressure gradients on the basic structure of a turbulent Mach 5.0 boundary layer were significant, therefore increasing the complexity of computational modeling.
Author: Center for Turbulence Research (U.S.)
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 410
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
We provide a summary of our accomplishments under a three-year 'mini URI' program in collaboration with researchers at Yale and Princeton universities. Whereas the central theme of the program is high Reynolds number wall-bounded turbulence, studies at Penn State included (1) analysis of fundamental issues of scale interactions in high Reynolds number turbulence dynamics, (2) the use of the wavelet decomposition and generalized filtering techniques in describing the relationship between the Fourier-spectral description of scale and the physical-space description of structure, (3) direct numerical simulation of passive scalar sources in low Reynolds number turbulent boundary layers and analysis of scalar evolution in relationship to laboratory data, (4) the relationship between homogeneous turbulent shear flow and the inertial sublayer in high Reynolds number turbulent boundary layers, and (5) the development and application of sophisticated data analysis techniques which intimately combine graphical and quantitative analysis within a fully interactive 'Analytical Environment'. A brief summary of the accomplishments in each area of development is presented. Turbulence, Turbulent boundary layers, Shear flows.
