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Book Numerical Simulation of 3 D Shock Wave Turbulent Boundary Layer Interaction Using a Two Equation Model of Turbulence

Download or read book Numerical Simulation of 3 D Shock Wave Turbulent Boundary Layer Interaction Using a Two Equation Model of Turbulence written by Marianna Gnedin and published by . This book was released on 1996 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Shock Wave Boundary Layer Interactions

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.

Book Three dimensional Shock Wave turbulent Boundary Layer Interactions at Mach 6

Download or read book Three dimensional Shock Wave turbulent Boundary Layer Interactions at Mach 6 written by C. Herbert Law and published by . This book was released on 1975 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results of an investigation of the three-dimensional interaction between a skewed shock wave and a turbulent boundary layer are presented. Surface pressure and heat transfer distributions and oil flow photographs were obtained at a freestream Mach number of 5.85 and two Reynolds numbers of ten and twenty million per foot. The model configuration consisted of a shock generator mounted perpendicularly to a flat plate. The shock generator leading edge was sharp and nonswept and intersected the flat plate surface about 8.5 inches downstream of the flat plate leading edge. The shock generator surface was 7.55 inches long and 3 inches high and its angle to the freestream flow was adjusted from 4 to 20 degrees. The generated shock waves were of sufficient strength to produce turbulent boundary layer separation on the flat plate surface.

Book Understanding and Predicting Shockwave and Turbulent Boundary Layer Interactions

Download or read book Understanding and Predicting Shockwave and Turbulent Boundary Layer Interactions written by M. Pino Martin and published by . This book was released on 2009 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shockwave and turbulent boundary layer interactions produce intense localized pressure loads and heating rates that can have a dramatic influence on the drag and heating experienced by a high-speed vehicle, and can significantly impact fuel mixing and combustion in propulsion systems. The lack of standardized and traceable databases prevents the calibration of computational fluid dynamic models to accurately represent these critical flow phenomena. In this work we accomplished the development and validation against experiments at the same flow and boundary conditions of direct numerical simulations of shock and turbulent boundary layer interactions. We pioneered the development of a unique numerical capability that allows the accurate and detailed three-dimensional turbulence data at a reasonable turn-around time. In turn, parametric studies of fundamental flow physics are feasible, for the first time. By accurate, it is meant that the numerical uncertainty is within the experimental error.

Book Three Dimensional Unsteady Laminar Shock Wave Boundary Layer Interaction

Download or read book Three Dimensional Unsteady Laminar Shock Wave Boundary Layer Interaction written by and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Numerical Simulation of a Three dimensional Turbulent Boundary Layer

Download or read book Numerical Simulation of a Three dimensional Turbulent Boundary Layer written by Parviz Moin and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Numerical Simulation of Shock Turbulent Boundary Layer Interaction

Download or read book Numerical Simulation of Shock Turbulent Boundary Layer Interaction written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-11 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most flows of aerodynamic interest are compressible and turbulent. However, our present knowledge on the structures and mechanisms of turbulence is mostly based on incompressible flows. In the present work, compressibility effects in turbulent, high-speed, boundary layer flows are systematically investigated using the Direct Numerical Simulation (DNS) approach. Three-dimensional, time-dependent, fully nonlinear, compressible Navier-Stokes equations were numerically integrated by high-order finite-difference methods; no modeling for turbulence is used during the solution because the available resolution is sufficient to capture the relevant scales. The boundary layer problem deals with fully-turbulent compressible flows over flat geometries. Apart from its practical relevance to technological flows, turbulent compressible boundary layer flow is the simplest experimentally realizable turbulent compressible flow. Still, measuring difficulties prohibit a detailed experimental description of the flow, especially in the near-wall region. DNS studies provide a viable means to probe the physics of compressible turbulence in this region. The focus of this work is to explore the paths of energy transfer through which compressible turbulence is sustained. The structural similarities and differences between the incompressible and compressible turbulence are also investigated. The energy flow patterns or energy cascades are found to be directly related to the evolution of vortical structures which are generated in the near-wall region. Near-wall structures, and mechanisms which are not readily accessible through physical experiments are analyzed and their critical role on the evolution and the behavior of the flow is documented extensively. Biringen, Sedat and Hatay, Ferhat F. Unspecified Center NAG1-1472...

Book Physics and Numerical Simulation of Shock Wave turbulent Boundary layer Interactions

Download or read book Physics and Numerical Simulation of Shock Wave turbulent Boundary layer Interactions written by G. W. Heard and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions  Part 4

Download or read book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions Part 4 written by and published by . This book was released on 1986 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A theoretical model consists of the Reynolds-averaged 3-D compressible Navier-Stokes equations, with turbulence incorporated using the algebraic turbulent eddy viscosity model of Baldwin and Lomax, This year research efforts focused on both 2-D and 3-D turbulent interactions. A theoretical model was examined for a series of separated 2-D compression corner flows at Mach 2 and 3. Calculations were performed for four separate compression corners using 2-D compressible Navier-Stodes conde with MacCormack's hybrid algorithm. Results were compared to earlier computations using the Beam-Warming algorithm, and recent experiment data for turbulent Reynolds stresses. Calculated Reynolds stresses were observed to differ significantly from experimental measurements due to the inability of the turbulence model to incorporate the multiple scale effects of the turbulence structure downstream of reattachment. Computed results using the MacCormack hybrid algorithm were observed to be insensitive to the Courant number. The 3-D turbulence interactions research concentrated on the 3-D sharp fin and on the 3-D swept compression corner. In the former case, the computed flowfield for the 20 deg sharp fin at Mach 3 and a Reynolds number of 930,000 was compared with the calculated results of Horstman (who used the Jones-Launder turbulence model) and experimental data of the Princeton Gas Dynamics Lab. Overall comparison with experiment was very good.

Book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions  Part 2

Download or read book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions Part 2 written by and published by . This book was released on 1983 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of the research effort is the understanding of three-dimensional shock wave-turbulent boundary layer interactions. The approach uses the full mean compressible Navier-Stokes equations with turbulence incorporated through the algebraic turbulent eddy viscosity model of Baldwin and Lomax. During the present year of the research effort, the three-dimensional shock boundary layer interaction generated by a 10 deg sharp fin has been computed at Mach 3 for a Reynolds number 280000. These results, together with previous computations of the same configuration at Reynolds number = 930000, are compared with experimental data for pitot pressure and yaw angle. The agreement with the experimental data is good, and the theory accurately predicts the recovery of the boundary layer downstream of the interaction of Reynolds number = 280000. The computed flowfield is employed to analyze the structure of the 3-D interaction through contour plots of flow variables. Also, during the present year, the investigation of the 2-D turbulent supersonic compression corner at Mach 3 was completed. The relaxation modification to the Baldwin-Lomax model was found to yield reasonably accurate predictions of the upstream propagation of the surface for the Reynolds number range investigated. An additional computation at Mach 2 was performed, and the results were in general in agreement with the previous conclusions. (Author).

Book Numerical Simulation of Viscous Shock Layer Flows

Download or read book Numerical Simulation of Viscous Shock Layer Flows written by Y.P. Golovachov and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is concerned with mathematical modelling of supersonic and hyper sonic flows about bodies. Permanent interest in this topic is stimulated, first of all, by aviation and aerospace engineering. The designing of aircraft and space vehicles requires a more precise prediction of the aerodynamic and heat transfer characteristics. Together with broadening of the flight condition range, this makes it necessary to take into account a number of gas dynamic and physical effects caused by rarefaction, viscous-inviscid interaction, separation, various physical and chemical processes induced by gas heating in the intensive bow shock wave. The flow field around a body moving at supersonic speed can be divided into three parts, namely, shock layer, near wake including base flow, and far wake. The shock layer flow is bounded by the bow shock wave and the front and lat eral parts of the body surface. A conventional approach to calculation of shock layer flows consists in a successive solution of the inviscid gas and boundary layer equations. When the afore-mentioned effects become important, implementation of these models meets difficulties or even becomes impossible. In this case, one has to use a more general approach based on the viscous shock layer concept.

Book The Modeling of a Three dimensional Shock Wave Turbulent Boundary Layer Interaction

Download or read book The Modeling of a Three dimensional Shock Wave Turbulent Boundary Layer Interaction written by S. Bogdonoff and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Direct Numerical Simulation of Compressible Turbulent Flows  Using Adaptive Spectral Element Method

Download or read book Direct Numerical Simulation of Compressible Turbulent Flows Using Adaptive Spectral Element Method written by and published by . This book was released on 1994 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this final report covering the period 1993-1994, the preliminary results of the research on direct numerical simulation of compressible turbulent flows are presented. Specifically, the adaptive Legendre polynomial spectral element method with the mixed explicit-implicit(MEI) Taylor-Galericin formulation is used in order to capture detailed physics involved in three-dimensional shock wave turbulent boundary layer interactions. (AN).

Book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions

Download or read book Theoretical Investigation of Three Dimensional Shock Wave Turbulent Boundary Layer Interactions written by Doyle D. Knight and published by . This book was released on 1982 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of the research effort is the understanding of three-dimensional shock wave-turbulent boundary layer interactions. The approach uses the full mean compressible Navier-Stokes equations with turbulence incorporated through the algebraic turbulent eddy viscosity model of Baldwin and Lomax. During the present year of the research effort, the three-dimensional shock boundary layer interaction generated by a 10 deg sharp fin has been computed at Mach 3 for a Reynolds number 280000. These results, together with previous computations of the same configuration at Reynolds number = 930000, are compared with experimental data for pitot pressure and yaw angle. The agreement with the experimental data is good, and the theory accurately predicts the recovery of the boundary layer downstream of the interaction of Reynolds number = 280000. The computed flowfield is employed to analyze the structure of the 3-D interaction through contour plots of flow variables. Also, during the present year, the investigation of the 2-D turbulent supersonic compression corner at Mach 3 was completed. The relaxation modification to the Baldwin-Lomax model was found to yield reasonably accurate predictions of the upstream propagation of the surface for the Reynolds number range investigated. An additional computation at Mach 2 was performed, and the results were in general in agreement with the previous conclusions. (Author).

Book Numerical Simulations of the Shock Wave boundary Layer Interactions

Download or read book Numerical Simulations of the Shock Wave boundary Layer Interactions written by Ismaïl Ben Hassan Saïdi and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Situations where an incident shock wave impinges upon a boundary layer are common in the aeronautical and spatial industries. Under certain circumstances (High Mach number, large shock angle...), the interaction between an incident shock wave and a boundary layer may create an unsteady separation bubble. This bubble, as well as the subsequent reflected shock wave, are known to oscillate in a low-frequency streamwise motion. This phenomenon, called the unsteadiness of the shock wave boundary layer interaction (SWBLI), subjects structures to oscillating loads that can lead to damages for the solid structure integrity.The aim of the present work is the unsteady numerical simulation of (SWBLI) in order to contribute to a better understanding of the SWBLI unsteadiness and the physical mechanism causing these low frequency oscillations of the interaction zone.To perform this study, an original numerical approach is used. The one step Finite Volume approach relies on the discretization of the convective fluxes of the Navier Stokes equations using the OSMP scheme developed up to the 7-th order both in space and time, the viscous fluxes being discretized using a standard centered Finite-Difference scheme. A Monotonicity-Preserving (MP) constraint is employed as a shock capturing procedure. The validation of this approach demonstrates the correct accuracy of the OSMP scheme to predict turbulent features and the great efficiency of the MP procedure to capture discontinuities without spoiling the solution and with an almost negligible additional cost. It is also shown that the use of the highest order tested of the OSMP scheme is relevant in term of simulation time and accuracy compromise. Moreover, an order of accuracy higher than 2-nd order for approximating the diffusive fluxes seems to have a negligible influence on the solution for such relatively high Reynolds numbers.By simulating the 3D unsteady interaction between a laminar boundary layer and an incident shock wave, we suppress the suspected influence of the large turbulent structures of the boundary layer on the SWBLI unsteadiness, the only remaining suspected cause of unsteadiness being the dynamics of the separation bubble. Results show that only the reattachment point oscillates at low frequencies characteristic of the breathing of the separation bubble. The separation point of the recirculation bubble and the foot of the reflected shock wave have a fixed location along the flat plate with respect to time. It shows that, in this configuration, the SWBLI unsteadiness is not observed.In order to reproduce and analyse the SWBLI unsteadiness, the simulation of a shock wave turbulent boundary layer interaction (SWTBLI) is performed. A Synthetic Eddy Method (SEM), adapted to compressible flows, has been developed and used at the inlet of the simulation domain for initiating the turbulent boundary layer without prohibitive additional computational costs. Analyses of the results are performed using, among others, the snapshot Proper Orthogonal Decomposition (POD) technique. For this simulation, the SWBLI unsteadiness has been observed. Results suggest that the dominant flapping mode of the recirculation bubble occurs at medium frequency. These cycles of successive enlargement and shrinkage of the separated zone are shown to be irregular in time, the maximum size of the recirculation bubble being submitted to discrepancies between successive cycles. This behaviour of the separation bubble is responsible for a low frequency temporal modulation of the amplitude of the separation and reattachment point motions and thus for the low frequency breathing of the separation bubble. These results tend to suggest that the SWBLI unsteadiness is related to this low frequency dynamics of the recirculation bubble; the oscillations of the reflected shocks foot being in phase with the motion of the separation point.