Download or read book Instabilities and Transition in Three Dimensional Boundary Layers with Emphasis on Gas Turbine Blade Flows written by and published by . This book was released on 2000 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Absolute instability of (Gortler vortices on the severely curved concave pressure side of a gas-turbine blade is the main thrust of the third-year work under this grant. For the most part, the Gortler vortices have been investigated in an incompressible boundary layer over thin-wing sections or artificial inserts on an otherwise flat plate. The cascade of modem aircraft engines operate in the high subsonic Mach number regime with velocity fields strongly affected by centrifugal forces maintained by the large curvature of profiles. Unsteady spiral-type vortices developing in these environments provoke the absolute instability in the streamwise direction of the boundary layer leading to earlier transition. An effort undertaken after the meeting in Shalimar (May 29-31, 2002) show that the heat transfer coefficient is even more susceptible to enhancing oscillations in the upstream moving wave packets than the pressure.
Download or read book Research on Instabilities and Transition in Three Dimensional Boundary Layers with Emphasis on Gas Turbine Blade Flows written by and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Absolute instability of (Gortler vortices on the severely curved concave pressure side of a gas-turbine blade is the main thrust of the third-year work under this grant. For the most part, the Gortler vortices have been investigated in an incompressible boundary layer over thin-wing sections or artificial inserts on an otherwise flat plate. The cascade of modern aircraft engines operate in the high subsonic Mach number regime with velocity fields strongly affected by centrifugal forces maintained by the large curvature of profiles. Unsteady spiral-type vortices developing in these environments provoke the absolute instability in the streamwise direction of the boundary layer leading to earlier transition. An effort undertaken after the meeting in Shalimar (May 29-31, 2002) show that the heat transfer coefficient is even more susceptible to enhancing oscillations in the upstream moving wave packets than the pressure.
Download or read book Research on Instabilities Separation and Transition in Three Dimensional Boundary Layers with Emphasis on Gas Turbine Blade Flows written by and published by . This book was released on 2005 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1. Gortler vortices on the concave pressure side of a blade; 2. Laminar/turbulent transition on the convex side of a blade; 3. Turbulent separation under the action of the strong adverse pressure gradient; 4. Cooling-film aerodynamics.
Download or read book Flow Transition in Gas Turbine Airfoil Boundary Layers written by Gregory S. West and published by . This book was released on 1985 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reshotko has suggested that transition may be viewed as the response of a very complex three-dimensional nonlinear oscillator (the laminar boundary layer) to a random and often statistically nonuniform forcing function (the disturbances). The first objective of this study concerns the phenomenon of flow transition in boundary layers on turbine airfoils--from the onset of turbulence to the transition completion. Transition studies, though fundamental to fluid mechanics, are unique in gas turbine cascades because of the compounding factors that act not in individual isolation, but as a collective group and that constitute by-pass mechanisms not amenable to linear analyses from a mathematical point of view. The second objective is to evolve an engineering method to account for surface roughness effects on heat transfer and turbulent boundary layer analyses, which have heretofore been studied in fragments. Transition prediction in gas turbine boundary layer flows is critical in assessing the cooling requirements for gas turbine vanes and blades. This report summarizes the classical, fundamental findings in transition prediction for simplified geometrics and discusses empirical rules currently in use for gas turbine environments. Keywords: Airfoil boundary layer transition.
Download or read book Transition in Turbines written by and published by . This book was released on 1985 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Final Report on Three dimensional Structure of Transitional Boundary Layers written by William S. Saric and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Instability Transition and Turbulence written by M. Yousuff Hussaini and published by . This book was released on 1992 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Boundary Layer Theory written by Herrmann Schlichting and published by Springer Science & Business Media. This book was released on 2003-05-20 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new edition of the almost legendary textbook by Schlichting completely revised by Klaus Gersten is now available. This book presents a comprehensive overview of boundary-layer theory and its application to all areas of fluid mechanics, with emphasis on the flow past bodies (e.g. aircraft aerodynamics). It contains the latest knowledge of the subject based on a thorough review of the literature over the past 15 years. Yet again, it will be an indispensable source of inexhaustible information for students of fluid mechanics and engineers alike.
Download or read book On the Stability of Three Dimensional Boundary Layers written by Erik Janke and published by . This book was released on 1999 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow Transition in Gas Turbine Airfoil Boundary Layers Fundamentals and Empiricisms written by and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reshotko has suggested that transition may be viewed as the response of a very complex three-dimensional nonlinear oscillator (the laminar boundary layer) to a random and often statistically nonuniform forcing function (the disturbances). The first objective of this study concerns the phenomenon of flow transition in boundary layers on turbine airfoils--from the onset of turbulence to the transition completion. Transition studies, though fundamental to fluid mechanics, are unique in gas turbine cascades because of the compounding factors that act not in individual isolation, but as a collective group and that constitute by-pass mechanisms not amenable to linear analyses from a mathematical point of view. The second objective is to evolve an engineering method to account for surface roughness effects on heat transfer and turbulent boundary layer analyses, which have heretofore been studied in fragments. Transition prediction in gas turbine boundary layer flows is critical in assessing the cooling requirements for gas turbine vanes and blades. This report summarizes the classical, fundamental findings in transition prediction for simplified geometrics and discusses empirical rules currently in use for gas turbine environments. Keywords: Airfoil boundary layer transition.
Download or read book On Stability Transition and Turbulence in Three dimensional Boundary layer Flows written by and published by . This book was released on 2015 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Three Dimensional Structure of Boundary Layers in Transition to Turbulence written by Thorwald Herbert and published by . This book was released on 1986 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unified theory of secondary instability in wall-bound shear flows has been developed. This theory rests on Floquet systems of stability equations and permits classification and quantitative analysis of different modes of secondary instability in the three-dimensional stage of laminar-turbulent transition. The catalogue of solutions is consistent with observations and predicts other phenomena that have not been identified in experiments. The theoretical results have been used to reproduce patterns in flow visualizations by computer animation. Analysis of the energy balance has shown a feedback loop between mean flow, two-dimensional, and three-dimensional disturbances that is considered key to the process of self-sustained transition. Various techniques have been developed to investigate details of the nonlinear three-dimensional processes involved in this feedback loop. Keywords: Boundary layer, Stability, Transition.
Download or read book Experimental Studies in Three dimensional Turbulent Boundary Layers written by J. P. Johnston and published by . This book was released on 1976 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: The various methods for measurement of the six components of the turbulence stress tensor are reviewed, and some of the data on the turbulent shear stress vector are presented to demonstrate the validity of current ideas for.
Download or read book Effect of Distributed Three dimensional Roughness and Surface Cooling on Boundary layer Transition and Lateral Spread of Turbulence at Supersonic Speeds written by Albert L. Braslow and published by . This book was released on 1959 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stability of Three dimensional Compressible Boundary Layers written by Eli Reshotko and published by . This book was released on 1962 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Three dimensional Turbulent Boundary Layers written by Anthony John Wheeler and published by . This book was released on 1972 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Studies on Laminar turbulent Transition in Boundary Layers written by Kyung Soo Yang and published by . This book was released on 1988 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
