Download or read book A Multiple view Visual Study of the Inner outer Region Interactions of Coherent Motions in a Turbulent Boundary Layer written by Kue Pan and published by . This book was released on 1992 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1984 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Interactions Between the Inner and Outer Region Motions in Turbulent Boundary Layers written by Joseph Charles Klewicki and published by . This book was released on 1989 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Boundary Layer Inner Outer Interactions written by and published by . This book was released on 1993 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: A summary of work performed to study the interactions between the inner and outer regions of a turbulent boundary layer is presented. The interactions were studied by observing the response of the boundary layer to different perturbations. The inner region was modified by adding surface roughness, and the outer region suppressed using LEBU's. Velocity measurements were made with a three component LDV, a scanning LDV, and an X-type hot-film probe. The scanning LDV was developed to obtain continuous time history measurements of instantaneous velocity profiles down to y+ = 10. Details of the structure of bursts, sweeps, and shear layers over smooth and rough walls were determined using conditional sampling with simultaneous measurements from a detector probe and a mapping probe. This allowed the mapping of the complete three-dimensional structure of the three-component velocity field for these structures. Both single point detection, using quadrant and VITA techniques, and a unique spatially coherent structure detection technique were used. The spatial detection technique developed in this project takes advantage of the two- dimensional velocity field information obtained from the scanning LDV. Scanning laser doppler velocimeter, Burst, Sweep, Shear layer large scale structure.
Download or read book A Study of Intermediate Scale Motions in the Outer Region of Turbulent Boundary Layers written by David Bruce Signor and published by . This book was released on 1982 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Production of Turbulence in Boundary Layers The Role of Microscale Coherent Motions written by R. E. Falco and published by . This book was released on 1987 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: Details of the turbulence production process in turbulent boundary layers in the wall region have been clarified, especially the formation of the long streaky structure, and secondary hairpin vorticity. It appears that the outer region microscale coherent motion called a Typical eddy plays the dominant role in the process. Long time averaged statistics of the two point vorticity-vorticity correlations support the conditionally sampled data and interpretations. The typical eddy produces the long streaks along with the pockets, and one of the hairpins directly. Several other hairpins form from the evolution of the vorticity produced by the passage of the typical eddy over the wall. A model of the typical eddy/wall region interaction, i.e., a vortex ring/Stokes layer interaction, was investigated to see if it could reproduce all of the morphology. It was found that the model can produce all of the turbulent boundary layer features associated with production, including the long streaks. By using the model, we have gained new insights into the sensitivity of the production process. Relatively small differences in the convection velocity of the excitation eddies have been found to result in the difference between turbulent boundary layer production and spot production (which involves very strong lateral production). Our data suggest that there are many combinations of parameters that can result in critical conditions.
Download or read book The Kinematics of Turbulent Boundary Layer Structure written by Stephen Kern Robinson and published by . This book was released on 1991 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Characteristics of Turbulent Boundary Layers in Rapidly Accelerated Flows written by Paul F. Brinich and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analysis of time-mean-turbulent boundary layer velocity profiles measured in a rapidly accelerating flow suggests that the outer region of the velocity profiles consists of essentially inviscid, rotational flow. The extent of this inviscid outer region was observed in some cases to exceed 90 percent of what is ordinarily thought of as the turbulent boundary layer thickness. On the other hand, the inner frictional region of these velocity profiles appears to have turbulent characteristics similar to those of more conventional turbulent boundary layers. Hence, the outer edge boundary condition for this inner region is more properly the external rotational flow region than the free stream.
Download or read book Inner outer Interactions in a Rough wall Turbulent Boundary Layer written by Gokul Pathikonda and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Workshop on Coherent Structure of Turbulent Boundary Layers written by Charles Robert Smith and published by . This book was released on 1981 with total page 1116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Turbulent Boundary Layer Structure written by John Leask Lumley and published by . This book was released on 1986 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theoretical Experimental Investigation of Coherent Structure in the Turbulent Boundary Layer written by and published by . This book was released on 1982 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program combines both experimental flow visualization studies with analytical investigations of a series of phenomenological and theoretical models based upon three-dimensional, vortical flow structures developing and interacting in proximity to a solid surface. The experimental program considered a range of sub-problems including the effect of surface modifications on low-speed streak formation and drag, and the effect of vortex loop inter-action with a solid boundary. To augment visual studies, a computerized interface with the video system has been developed which allows quantitative data to be obtained from flow visualization pictures. The specific thrust of the theoretical studies has been focussed on three areas: (1) how two and three-dimensional vortex structures interact with wall boundary layers; (2) the development of a new type of prediction method for two-dimensional turbulent boundary-layer flows; and (3) improvement in numerical techniques for solving parabolic, boundary-layer equations.
Download or read book Experimental Study of Coherent Events in Laminar and Turbulent Boundary Layers written by William Thomas Hambleton and published by . This book was released on 2007 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characteristics of Turbulence in a Boundary Layer with Zero Pressure Gradient written by P. S. Klebanoff and published by . This book was released on 1954 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of an experimental investigation of a turbulent boundary layer with zero pressure gradient are presented. Measurements with the hot-wire anemometer were made of turbulent energy and turbulent shear stress, probability density and flattening factor of u-fluctuation (fluctuation in x-direction), spectra of turbulent energy and shear stress, and turbulent dissipation. The importance of the region near the wall and the inadequacy of the concept of local isotropy are demonstrated. Attention is given to the energy balance and the intermittent character of the outer region of the boundary layer. Also several interesting features of the spectral distribution of the turbulent motions are discussed.
Download or read book Turbulent Boundary Layers written by Helmut E. Weber and published by . This book was released on 1979 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Workshop on Coherent Structure of Turbulent Boundary Layers written by C. R. Smith and published by . This book was released on 1978 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: A discussion of the role of visual and probe measurements in turbulent structure research is given, stressing the constraining limitations of each and the interrelationships of the two methods. A selective history of the use of visual results is discussed in terms of the constraining limitations of the visual methods. Retrospective remarks are presented concerning the Stanford visual data on the inner portions of turbulent boundary layer structure. The final section discusses some general features of what is currently known about the structure of turbulent boundary layers, draws conclusions from this general knowledge, and poses questions that seem currently important in gaining further understanding. The paper stresses overall aspects of the structure problem at the expense of details in an attempt to gain perspective. (Author).
Download or read book Inner and Outer layer Effects on the Dynamics of a Turbulent Boundary Layer written by Ahmed Moustafa Naguib and published by . This book was released on 1992 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
