Download or read book A Comprehensive Study of Vortex Breakdown Flow Mechanisms Computational Investigation and Preliminary Control written by and published by . This book was released on 2004 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: A modified vortex filament method is used to simulate the evolution of the transient formation of vortex breakdown. The method supports previous studies, illustrating that vortex breakdown. The method supports previous studies, illustrating that vortex breakdown is initiated by a negative vorticity gradient which triggers an inviscid self-induction feedback mechanism and when subsequently subjected to viscous effects, results in steady state vortex breakdown. The results of the method are first validated experimentally with numerous past dye flow visualization and particle image velocimetry investigations, and then used to qualitatively investigate the self-induction flow mechanisms during the formative stages of stages of transient breakdown. As a complement to the qualitative investigation, a quantitative analysis is performed, which yields a local and dynamical relationship relating the azimuthal vorticity gradient at a particular location to the curvature of the instantaneous streamline, projected onto the meridional plane, at the same location. This relationship further shows that once radial expansion commences in the region of negative azimuthal vorticity, it continues to expand such that the meridional streamline becomes more curved with time, supporting that the negative vorticity gradient not only initiates the radial expansion, but also, feeds its subsequent growth. On the contrary, in the region of a positive gradient, the streamline continues to flatten fostering radial contraction of the vortex tube, which provides a closure to expansion. In attempt to suppress breakdown in two preliminary control simulations, this positive azimuthal vorticity gradient is then introduced to the vortex flow just prior to breakdown. Results from these control simulations illustrated a temporal and spatial delay in breakdown as well as exhibiting flow behavior associated with complete elimination of breakdown.
Download or read book A Comprehensive Study of Vortex Breakdown Flow Mechanisms written by William Frederick Johnson and published by . This book was released on 2004 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Study of Vortex Breakdown in Circular Tube written by Jiunn-Chi Wu and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Studies of Vortex Breakdown written by G. Paul Neitzel 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 A Computational Study of the Taxonomy of Vortex Breakdown written by Robert E. Spall and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Mechanism for Vortex Breakdown and Some Measures for Its Control written by Michael Charles Jones and published by . This book was released on 2002 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of Vortex Breakdown and Its Control in Swirling Flow written by Dina Fastovsky and published by . This book was released on 2007 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Active Feedback Flow Control Theory of the Vortex Breakdown Process written by Joshua Granata and published by . This book was released on 2014 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis and Control of Supersonic Vortex Breakdown Flows written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-06 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis and computation of steady, compressible, quasi-axisymmetric flow of an isolated, slender vortex are considered. The compressible, Navier-Stokes equations are reduced to a simpler set by using the slenderness and quasi-axisymmetry assumptions. The resulting set along with a compatibility equation are transformed from the diverging physical domain to a rectangular computational domain. Solving for a compatible set of initial profiles and specifying a compatible set of boundary conditions, the equations are solved using a type-differencing scheme. Vortex breakdown locations are detected by the failure of the scheme to converge. Computational examples include isolated vortex flows at different Mach numbers, external axial-pressure gradients and swirl ratios. Kandil, Osama A. Unspecified Center...
Download or read book A Study of the Mechanisms of Axisymmetric Vortex Breakdown written by David Louis Darmofal and published by . This book was released on 1994 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Computational Model of Vortex Breakdown in Density Stratified Flows written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation Into Vortex Breakdown and Vortex Breakdown Control written by Sammy Khalil and published by . This book was released on 2006 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of Vortex Breakdown in Multiphase Pipe Flow written by Ronald J. Hugo and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Studies of Vortex Breakdown written by and published by . This book was released on 1992 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Axisymmetric vortex breakdown was simulated numerically within an enclosed circular cylinder with: (1) fixed cylindrical wall-endwall and one rotating lid; and (2) rotating cylindrical wall-endwall with a differentially rotating lid. Variations of the two dynamical parameters permitted the calculation of cases in which incipient vortex breakdown was observed. A vortex breakdown criterion recently proposed by Brown & Lopez was tested against these numerical solutions.
Download or read book Application of Computational Fluid Dynamics to the Study of Vortex Flow Control for the Management of Inlet Distortion written by Bernhard H. Anderson and published by . This book was released on 1992 with total page 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 1995 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book NASA SP written by and published by . This book was released on 1993 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
