Download or read book Control of Separation for Turbulent Boundary Layers Subjected to Wall Curvature and Streamwise Pressure Gradients written by Hermann F. Fasel and published by . This book was released on 2005 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Control of Separation for Turbulent Boundary Layers Subjected to Wall Curvature and Streamwise Pressure Gradients written by and published by . This book was released on 2005 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low Pressure Turbine (LPT) stages are important for modern jet engines, and in particular for engines used in Unmanned Aerial Vehicles (UAV). At low operating Reynolds numbers boundary layers remain laminar over a large downstream extent of LPT blades. Laminar boundary layer separation can cause significant reductions in turbine and overall engine performance. In an experimental research program at the Air Force Research Laboratory (AFRL), the potential advantages of Active Flow Control (AFC) for separation control were systematically explored. In collaboration with the experimental effort, we performed numerical investigations of AFC for LPT separation to investigate the relevant physical mechanisms. Numerical simulations can provide insight into flow details that is not possible in experiments. We chose a two-pronged approach: A computationally less efficient but more versatile finite volume code was employed for simulations of the full geometry. Open-loop control strategies were explored in 2-D calculations. Detailed investigations of the VGJ actuation for a flat plate model problem were performed with a very efficient finite difference code. The high-resolution DNS helped identify some of the key physical mechanisms responsible for the effectiveness of VGJs.
Download or read book Longitudinal Vortices in Turbulent Boundary Layers Subjected to Wall Curvature and Strong Adverse Pressure Gradients Numerical Investigations Using LES and DNS written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Longitudinal vortices in turbulent boundary layers that are subjected to strong wall curvature (both convex and concave) and strong adverse pressure gradients were investigated numerically. The motivation for this research was to uncover the fundamental mechanisms responsible for the generation of longitudinal vortices and their dynamical interaction with the other dominant coherent structures that arise from the presence of wall curvature and strong adverse pressure gradients. This understanding is essential for future implementation of separation control techniques for practical flows when longitudinal vortices are inherently present, or when forced longitudinal vortices are employed for separation control (i.e., on demand vortex generators). Furthermore, such investigations can shed light on the turbulence generation mechanisms for boundary layers subjected to streamwise curvature and pressure gradients when longitudinal vortices are present. The investigations were carried out using DNS, LES and unsteady RANS. Towards this end, we have employed our new Flow Simulation Methodology (FSM) for calculating turbulent flows. The present numerical investigations were a critical test for FSM and the turbulence model used in FSM as the investigated flows are highly complex with the turbulence in strong non-equilibrium.
Download or read book Boundary Layer Theory written by Hermann Schlichting (Deceased) and published by Springer. This book was released on 2016-10-04 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition of the near-legendary textbook by Schlichting and revised by Gersten presents a comprehensive overview of boundary-layer theory and its application to all areas of fluid mechanics, with particular emphasis on the flow past bodies (e.g. aircraft aerodynamics). The new edition features an updated reference list and over 100 additional changes throughout the book, reflecting the latest advances on the subject.
Download or read book Progress in Turbulence VIII written by Ramis Örlü and published by Springer Nature. This book was released on 2019-08-27 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume collects the edited and reviewed contributions presented in the 8th iTi Conference on Turbulence, held in Bertinoro, Italy, in September 2018. In keeping with the spirit of the conference, the book was produced afterwards, so that the authors had the opportunity to incorporate comments and discussions raised during the event. The respective contributions, which address both fundamental and applied aspects of turbulence, have been structured according to the following main topics: I TheoryII Wall-bounded flowsIII Simulations and modellingIV ExperimentsV Miscellaneous topicsVI Wind energy/div
Download or read book Boundary Layer and Flow Control written by G. V. Lachmann and published by Elsevier. This book was released on 2014-05-12 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt: Boundary Layer and Flow Control: Its Principles and Application, Volume 2 focuses on the layer of fluid in the immediate area of a bounding surface where the effects of viscosity are substantial. This book is organized into two main topics—boundary layer control for low drag, and shock-induced separation and its prevention by design and boundary layer control. It specifically discusses the nature of transition, effect of two-dimensional and isolated roughness on laminar flow, and progress in the design of low drag aerofoils. The onset of separation effects for aerofoils and wings, shock-induced separation for laminar boundary layers, and shock-induced separation for laminar boundary layers are also deliberated. This volume is recommended to physicists and specialists interested in boundary layer and flow control.
Download or read book Adverse Pressure Gradient and Separating Turbulent Boundary layer Flows written by Andrew D. Cutler and published by . This book was released on 1984 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compressible Turbulent Boundary Layer Computations for Flow with Longitudinal Curvature written by Walter B. Sturek and published by . This book was released on 1975 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A numerical study has been performed using a finite-difference boundary layer computer program that includes corrections to the equations of motion for longitudinal curvature and allows the static pressure to be specified as a known function of x and y. Calculations with and without the corrections for longitudinal curvature and pressure gradient normal to be the local surface have been compared to experimental measurements of a supersonic turbulent boundary layer flow over a surface with concave longitudinal curvature. Substantially improved agreement with experimental measurements is obtained for the calculations including corrections for wall curvature and pressure gradient normal to the local surface for density profile, skin friction coefficient, and boundary-layer integral properties.
Download or read book Shock Wave Boundary Layer Interactions written by Holger Babinsky and published by Cambridge University Press. This book was released on 2011-09-12 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock wave-boundary-layer interaction (SBLI) is a fundamental phenomenon in gas dynamics that is observed in many practical situations, ranging from transonic aircraft wings to hypersonic vehicles and engines. SBLIs have the potential to pose serious problems in a flowfield; hence they often prove to be a critical - or even design limiting - issue for many aerospace applications. This is the first book devoted solely to a comprehensive, state-of-the-art explanation of this phenomenon. It includes a description of the basic fluid mechanics of SBLIs plus contributions from leading international experts who share their insight into their physics and the impact they have in practical flow situations. This book is for practitioners and graduate students in aerodynamics who wish to familiarize themselves with all aspects of SBLI flows. It is a valuable resource for specialists because it compiles experimental, computational and theoretical knowledge in one place.
Download or read book A Study of Three Dimensional Turbulent Boundary Layer Separation and Vortex Flow Control Using the Reduced Navier Stokes Equations written by and published by . This book was released on 1991 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Turbulent Flows with Computer Programs written by Tuncer Cebeci and published by Elsevier. This book was released on 2004 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modelling and Computation of Turbulent Flows has been written by one of the most prolific authors in the field of CFD. Professor of aerodynamics at SUPAERO and director of DMAE at ONERA, the author calls on both his academic and industrial experience when presenting this work. The field of CFD is strongly represented by the following corporate companies; Boeing; Airbus; Thales; United Technologies and General Electric, government bodies and academic institutions also have a strong interest in this exciting field. Each chapter has also been specifically constructed to constitute as an advanced textbook for PhD candidates working in the field of CFD, making this book essential reading for researchers, practitioners in industry and MSc and MEng students. * A broad overview of the development and application of Computational Fluid Dynamics (CFD), with real applications to industry * A Free CD-Rom which contains computer program's suitable for solving non-linear equations which arise in modeling turbulent flows * Professor Cebeci has published over 200 technical papers and 14 books, a world authority in the field of CFD
Download or read book Analysis of Turbulent Boundary Layers written by Tuncer Cebeci and published by Elsevier. This book was released on 2012-12-02 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis of Turbulent Boundary Layers focuses on turbulent flows meeting the requirements for the boundary-layer or thin-shear-layer approximations. Its approach is devising relatively fundamental, and often subtle, empirical engineering correlations, which are then introduced into various forms of describing equations for final solution. After introducing the topic on turbulence, the book examines the conservation equations for compressible turbulent flows, boundary-layer equations, and general behavior of turbulent boundary layers. The latter chapters describe the CS method for calculating two-dimensional and axisymmetric laminar and turbulent boundary layers. This book will be useful to readers who have advanced knowledge in fluid mechanics, especially to engineers who study the important problems of design.
Download or read book Incompressible Skewed Turbulent Boundary Layer on an End Wall of a Curved Two Dimensional Diffuser written by Marvin Dale Smith and published by . This book was released on 1970 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Research Briefs written by Center for Turbulence Research (U.S.) and published by . This book was released on 2010 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 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of Turbulent Boundary Layers Along Curved Surfaces written by Ronald M. C. So and published by . This book was released on 1972 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering Turbulence Modelling and Experiments 4 written by D. Laurence and published by Elsevier. This book was released on 1999-04-14 with total page 975 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings contain the papers presented at the 4th International Symposium on Engineering Turbulence Modelling and Measurements held at Ajaccio, Corsica, France from 24-26 May 1999. It follows three previous conferences on the topic of engineering turbulence modelling and measurements. The purpose of this series of symposia is to provide a forum for presenting and discussing new developments in the area of turbulence modelling and measurements, with particular emphasis on engineering-related problems. Turbulence is still one of the key issues in tackling engineering flow problems. As powerful computers and accurate numerical methods are now available for solving the flow equations, and since engineering applications nearly always involve turbulence effects, the reliability of CFD analysis depends more and more on the performance of the turbulence models. Successful simulation of turbulence requires the understanding of the complex physical phenomena involved and suitable models for describing the turbulent momentum, heat and mass transfer. For the understanding of turbulence phenomena, experiments are indispensable, but they are equally important for providing data for the development and testing of turbulence models and hence for CFD software validation.
