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Book A Numerical Study of Normal Shock Turbulent Boundary Layer Interactions

Download or read book A Numerical Study of Normal Shock Turbulent Boundary Layer Interactions written by Lowell C. Keel and published by . This book was released on 1979 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hybrid finite difference code developed by MacCormack was applied to the investigation of transonic normal-shock turbulent boundary layer interactions. The computations were performed for the half plane of a symetric two dimensional duct by establishing a symmetry boundary condition at the upper boundary. Both first and second order center line boudnary conditions were imposed with no measurable difference observed. A two-point linear extrapolation of the primative variable was unsuccessfully attempted at the subsonic outflow boundary, but a simple zero gradient condition gave satisfactory results at four different outflow boundary positions relative to the shock wave. Numerical results (M = 1.51, 1.40 and 1.3 Re = 3,000,000 per ft) were compared with the experimental data reported by Abbiss and East. Even though the data exhibit three-dimensional effects, the two-dimensional computations show agreement within approximately 10%. The differences observed in the numerical-experimental comparisons were all consistent with expected three-dimensional trends. Although not conclusive, the potential of adding simple three-dimensional corrections to the two-dimensional code shows promise for improving the experimental-numerical agreement. (Author).

Book Numerical Computation of Shock Wave turbulent Boundary Layer Interaction in Transonic Flow Over an Axisymmetric Curved Hill

Download or read book Numerical Computation of Shock Wave turbulent Boundary Layer Interaction in Transonic Flow Over an Axisymmetric Curved Hill written by S.-W. Kim and published by . This book was released on 1989 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Unsteadiness in Transonic Shock wave boundary Layer Interactions

Download or read book Unsteadiness in Transonic Shock wave boundary Layer Interactions written by Fulvio Sartor and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A transonic interaction between a shock wave and a turbulent boundary layer is experimentally and theoretically investigated. The configuration is a channel flow over a bump, where a shock wave causes the separation of the boundary layer and a recirculating bubble is observed downstream of the shock foot.The mean flow is experimentally investigated by means of PIV, then different techniques allows to identify the main unsteadiness of this shock-wave/boundary-layer interaction. As recognised in similar configurations, the flow presents two distinguished characteristic frequencies, whose origins are still unknown.Numerical simulations are performed solving RANS equations. Results are in good agreement with the experimental mean flow, but the approach fails to predict the unsteady. The solution of RANS equations is then considered as a base flow, and a global stability analysis is performed. Eigenvalue decomposition of the Navier-Stokes operator indicates that the interaction is stable, and the dynamics cannot be described by unstable global modes.A linearised approach based on a singular-value decomposition of the Resolvent is then proposed: the noise-amplifier behaviour of the flow is highlighted by the linearised approach. Medium-frequency perturbations are shown to be the most amplified in the mixing layer, whilst the shock wave behaves as a low-pass filter.The same approach is then applied to a transonic flow over a profile, where the flow can present high-amplitude shock oscillations. The stability analysis can describe both the buffet phenomenon when an unstable mode is present, and the convective instabilities responsible of medium-frequency unsteadiness.

Book Investigation of the Mechanism of Transonic Shock Wave Boundary Layer Interactions Using a Navier Stokes Analysis

Download or read book Investigation of the Mechanism of Transonic Shock Wave Boundary Layer Interactions Using a Navier Stokes Analysis written by D. V. Roscoe and published by . This book was released on 1984 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present report discusses the development of a time-dependent Navier-Stokes code for use in predicting transonic shock-wave boundary layer interaction. In addition, various test cases which have been performed are discussed. The algorithm used to solve the equations is based upon the consistently split linearized block implicit method of Briley and McDonald (15, 16). The philosophy and use of a solution adaptive mesh is also described. The test cases studied in this report are: normal shock wave boundary layer interaction in a constant area circular pipe, steady transonic flow over an axisymmetric bump, unsteady flow over an axisymmetric bump, supersonic flow over an axisymmetric compression corner and oblique shock wave impingement on a flat plate boundary layer. (Author).

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 Analysis of Imbedded Transonic Shock Wave Influence on Turbulent Boundary Layer Separation

Download or read book Analysis of Imbedded Transonic Shock Wave Influence on Turbulent Boundary Layer Separation written by J. E. Carter and published by . This book was released on 1982 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: A strong viscous-inviscid interaction model has been developed for predicting the detailed properties of the flow in the vicinity of an imbedded transonic shock wave interacting with a turbulent boundary layer in cases where the shock wave is of sufficient strength to result in flow separation. In this interaction model the inviscid flow is analyzed with a compressible stream function analysis specifically developed for mixed subsonic-supersonic flow regions. In the present effort this analysis has been extended to include upstream vorticity effects and the boundary-layer displacement effects. Numerous calculations are presented which demonstrates the capability of this analysis to predict transonic rotational flow. The viscous analysis in this interaction model is a newly developed inverse boundary-layer analysis which accounts for normal pressure gradients and imbedded shock waves. The equations are solved with a coupled implicit finite-difference scheme subject to the condition that the flow at the edge of viscous layer merges asymptotically with the outer inviscid flow. A model problem has been analyzed with this generalized inverse boundary-layer procedure and no stability problems were encountered.

Book Analysis of Transonic Shock Induced Separated Flow Including Normal Pressure Gradients

Download or read book Analysis of Transonic Shock Induced Separated Flow Including Normal Pressure Gradients written by and published by . This book was released on 1983 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analysis based on a two-layer interaction model is presented for the prediction of transonic shock-wave, boundary-layer interaction with emphasis on turbulent separated flow. In this analysis finite difference techniques are used to solve the viscous layer equations, expressed in a defect form, and the stream function-vorticity representation of the inviscid flow. A global technique is used to iteratively solve these coupled sets of equations. Normal pressure gradients and imbedded shock effects are included in the analysis. Two major conclusions can be drawn from the present work: First, favorable comparisons obtained with the separated data of Kooi (Mach no. = 1.4) demonstrate that the present analysis is capable of accurately resolving many of the transonic shock-wave, boundary-layer interaction. Second, these results show that, for transonic shock induced separation, the effect of displacement thickness interaction dominates over that produced by imbedded shock effects and normal pressure gradients. Calculations made with a modified algebraic turbulence model demonstrate that for separated cases the computed results are more sensitive to the turbulence model than to whether or not normal pressure gradients are included.

Book Transition Location Effect on Shock Wave Boundary Layer Interaction

Download or read book Transition Location Effect on Shock Wave Boundary Layer Interaction written by Piotr Doerffer and published by Springer Nature. This book was released on 2020-07-30 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents experimental and numerical findings on reducing shock-induced separation by applying transition upstream the shock wave. The purpose is to find out how close to the shock wave the transition should be located in order to obtain favorable turbulent boundary layer interaction. The book shares findings obtained using advanced flow measurement methods and concerning e.g. the transition location, boundary layer characteristics, and the detection of shock wave configurations. It includes a number of experimental case studies and CFD simulations that offer valuable insights into the flow structure. It covers RANS/URANS methods for the experimental test section design, as well as more advanced techniques, such as LES, hybrid methods and DNS for studying the transition and shock wave interaction in detail. The experimental and numerical investigations presented here were conducted by sixteen different partners in the context of the TFAST Project. The general focus is on determining if and how it is possible to improve flow performance in comparison to laminar interaction. The book mainly addresses academics and professionals whose work involves the aerodynamics of internal and external flows, as well as experimentalists working with compressible flows. It will also be of benefit for CFD developers and users, and for students of aviation and propulsion systems alike.

Book Physical Study of Shock wave boundary layer Interaction Control in Transonic Flow

Download or read book Physical Study of Shock wave boundary layer Interaction Control in Transonic Flow written by Reynald Bur and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Book Analytic Investigation of Transonic Normal Shock Boundary Layer Interaction

Download or read book Analytic Investigation of Transonic Normal Shock Boundary Layer Interaction written by W. H. Mason and published by . This book was released on 1974 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in inviscid transonic flow field computational capability and supercritical airfoil design make it important to understand of the the physics of normal shock-boundary layer interactions. In this work, the Navier-Stokes equations are thoroughly investigated through the use of perturbation methods and a generalized multi-region model is proposed for interactions between weak normal shock waves and turbulent boundary layers. This model is first applied to a highly idealized case in which a uniform subsonic flow is used to model the boundary layer, and analytic results for the wall and interface pressure are obtained.

Book Experimental and Analytical Investigation of Transonic Shock wave boundary layer Interaction Control with Three dimensional Bumps

Download or read book Experimental and Analytical Investigation of Transonic Shock wave boundary layer Interaction Control with Three dimensional Bumps written by Hideaki Ogawa and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Experiment on Transonic Shock wave Boundary layer Interaction

Download or read book Experiment on Transonic Shock wave Boundary layer Interaction written by J. W. Kooi and published by . This book was released on 1975 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Interaction of a Shock Wave with a Laminar Boundary Layer

Download or read book The Interaction of a Shock Wave with a Laminar Boundary Layer written by Theodore A. Reyhner and published by . This book was released on 1966 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: