Download or read book On the Nonlinear Development of the Most Unstable Goertler Vortex Mode written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1991 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fully Nonlinear Development of the Most Unstable Goertler Vortex in a Three Dimensional Boundary Layer written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1992 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fully Nonlinear Development of the Most Unstable Goertler Vortex in a Three Dimensional Boundary Layer written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-03 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nonlinear development is studied of the most unstable Gortler mode within a general 3-D boundary layer upon a suitably concave surface. The structure of this mode was first identified by Denier, Hall and Seddougui (1991) who demonstrated that the growth rate of this instability is O(G sup 3/5) where G is the Gortler number (taken to be large here), which is effectively a measure of the curvature of the surface. Previous researchers have described the fate of the most unstable mode within a 2-D boundary layer. Denier and Hall (1992) discussed the fully nonlinear development of the vortex in this case and showed that the nonlinearity causes a breakdown of the flow structure. The effect of crossflow and unsteadiness upon an infinitesimal unstable mode was elucidated by Bassom and Hall (1991). They demonstrated that crossflow tends to stabilize the most unstable Gortler mode, and for certain crossflow/frequency combinations the Gortler mode may be made neutrally stable. These vortex configurations naturally lend themselves to a weakly nonlinear stability analysis; work which is described in a previous article by the present author. Here we extend the ideas of Denier and Hall (1992) to the three-dimensional boundary layer problem. It is found that the numerical solution of the fully nonlinear equations is best conducted using a method which is essentially an adaption of that utilized by Denier and Hall (1992). The influence of crossflow and unsteadiness upon the breakdown of the flow is described. Otto, S. R. and Bassom, Andrew P. Unspecified Center NAS1-18605; NAS1-19480; RTOP 505-90-52-01...
Download or read book On the Instability of Goertler Vortices to Nonlinear Travelling Waves written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1990 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Nonlinear Development of the Most Unstable G rtler Vortex Mode written by James P. Denier and published by . This book was released on 1991 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fully Nonlinear Development of the Most Unstable G rtler Vortex in a Three Dimensional Boundary Layer written by S. R. Otto and published by . This book was released on 1992 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Secondary Instability of the Most Dangerous Goertler Vortex written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1993 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Onset of Three dimensionality and Time dependence in the Goertler Vortex Problem written by and published by . This book was released on 1987 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fully Nonlinear Development of the Most Unstable Gortler Vortex in a Three Dimensional Layer written by and published by . This book was released on 1992 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this article is to further our understanding of the effects of unsteadiness and crossflow upon the fully nonlinear development of unstable Gortler modes.
Download or read book Fully Nonlinear Development of the Most Unstable G rtler Vortex in a Three Dimensional Boundary Layer written by S. R. Otto and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Wall Compliance on the Goertler Vortex Instability written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1990 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Goertler Vortex Instability Mechanism in Three dimensional Boundary Layers written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1984 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Instability of Goertler Vortices to Nonlinear Traveling Waves written by and published by . This book was released on 1990 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent theoretical work has shown that strongly nonlinear, high wavenumber Gortler vortices developing within a boundary layer flow are susceptible to a secondary instability which takes the form of travelling waves confined to a thin region centered at the outer edge of the vortex. This work considered the case in which the secondary mode could be satisfactorily described by a linear stability theory and in the current paper our objective is to extend this investigation into the nonlinear regime. At this stage not only does the secondary mode become nonlinear but it also interacts with itself so as to modify the governing equations for the primary Gortler vortex. In this case then, the vortex and the travelling wave drive each other and, indeed, the whole flow structure is described by an infinite set of coupled, nonlinear differential equations. A Stuart-Watson type of weakly nonlinear analysis of these equations is undertaken and it concludes in particular, that on this basis there exist stable flow configurations in which the travelling mode is of finite amplitude. Impactions of our findings for practical situations are discussed and it is shown that the theoretical conclusions drawn here are in good qualitative agreement with available experimental observations.
Download or read book Goertler Vortices in Growing Boundary Layers written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-08 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Goertler vortices are thought to be the cause of transition in many fluid flows of practical importance. A review of the different stages of vortex growth is given. In the linear regime, nonparallel effects completely govern this growth, and parallel flow theories do not capture the essential features of the development of the vortices. A detailed comparison between the parallel and nonparallel theories is given and it is shown that at small vortex wavelengths, the parallel flow theories have some validity; otherwise nonparallel effects are dominant. New results for the receptivity problem for Goertler vortices are given; in particular vortices induced by free stream perturbations impinging on the leading edge of the walls are considered. It is found that the most dangerous mode of this type can be isolated and it's neutral curve is determined. This curve agrees very closely with the available experimental data. A discussion of the different regimes of growth of nonlinear vortices is also given. Again it is shown that, unless the vortex wavelength is small, nonparallel effects are dominant. Some new results for nonlinear vortices of 0(1) wavelengths are given and compared to experimental observations. Hall, Philip Unspecified Center...
Download or read book Fully Nonlinear Goertler Vortices in Constricted Channel Flows and Their Effect on the Onset of Separation written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1992 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Receptivity Problem for Goertler Vortices Vortex Motions Induced by Wall Roughness written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1990 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Goertler Vortices Wall Cooling and Gas Dissociation on the Rayleigh Instability in a Hypersonic Boundary Layer written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1991 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
