Download or read book Numerical Simulation of a Shock Wave turbulent Boundary Layer Interaction in a Duct written by Wei-Li Yang and published by . This book was released on 1992 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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:

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 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:

Download or read book Numerical Simulation of a Confined Transonic Normal Shock Wave turbulent Boundary Layer Interaction written by E. Blosch 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 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.

Download or read book A Numerical and Experimental Investigation of Multiple Shock Wave turbulent Boundary Layer Interactions in a Rectangular Duct written by Bruce Frederick Carroll and published by . This book was released on 1988 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Simulation of Three dimensional Shockwave turbulent boundary layer Interaction written by A. W. C. Leung and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Investigations of Turbulent Duct Flows Using Wall modeled Large eddy Simulation written by Zachary Phillips Vane and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The challenges posed by shock wave-turbulent boundary layer interactions (STBLIs) remain one of the primary considerations in the design and operation of air-breathing hypersonic vehicles. The internal flow within the isolator of a scramjet engine involves a series of coupled STBLIs. In order to study these phenomena, the interaction of a turbulent boundary layer with a shock train in a constant area duct (STCAD) is used as a model problem. Calculations of a STCAD are performed using wall-modeled Large-Eddy Simulation (WMLES). This approach reduces the computational cost of a simulation by modeling the inner portion of the boundary layer and thereby enables the calculation of high Reynolds number flows. The equilibrium formulation of the wall-model, which neglects the pressure gradient and convective terms in the thin boundary layer equations (TBLEs), is evaluated for a class of flows where the non-equilibrium characteristics are primarily exhibited outside of the wall-modeled region. Several modifications to the framework of the WMLES are also developed and tested in order to improve predictions for turbulent, non-circular duct flows. Results from calculations of a STCAD at lower Reynolds number are compared with previous wall-resolved LES investigations to establish confidence in the approach. The WMLES is then applied to a STCAD at the higher Reynolds number conditions from experiments where wall-resolved calculations were prohibitively expensive. A parameter study related to the physical characteristics of the interaction is performed to address the uncertainty created by the lack of experimental data with respect to the side wall boundary layers. The equilibrium WMLES is shown to provide accurate predictions in comparison with the experimental data measured in the spanwise center plane. The physics of the STCAD are shown to be strongly dependent on the three-dimensional confinement of the mean flow by the boundary layer as well as the pressure ratio across the interaction. Further studies explore the effects that the side wall boundary layers and variations in the Reynolds number have on the properties of the interaction. An investigation into the potential applicability of a reduced-order model to predict the general trends exhibited by the three-dimensional STCAD is also conducted.

Download or read book Direct Numerical Simulation of Shockwave and Turbulent Boundary Layer Interactions written by Minwei Wu and published by . This book was released on 2007 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the DNS analyses, the shock motion is characterized by a low frequency component (of order 0.01Uinfinity/delta). In addition, the motion of the shock is found to have two aspects: a spanwise wrinkling motion and a streamwise oscillatory motion. The spanwise wrinkling is observed to be a local feature with high frequencies (of order Uinfinity /delta). Two-point correlations reveal that the spanwise wrinkling is closely related to the low momentum motions in the incoming boundary layer as they convect through the shock. The low frequency shock motion is found to be a streamwise oscillation motion. Conditional statistics show that there is no significant difference in the mean properties of the incoming boundary layer when the shock is at an upstream or downstream location. However, analyses of the unsteadiness of the separation bubble reveal that the low frequency shock motion is driven by the downstream flow.

Download or read book Numerical Computations of Turbulence Amplification in Shock Wave Interactions written by Thomas A. Zang and published by . This book was released on 1983 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

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...

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:

Download or read book Numerical Simulations and Analyses of Shock Wave boundary Layer Interactions written by Avinash Jammalamadaka and published by . This book was released on 2013 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shock-boundary layer interaction (SBLI) is becoming one of the benchmark problems in the high-speed flow modeling and simulation community. The interaction of shock wave with the boundary layer is a very complex phenomenon that requires high-fidelity numerical methods like direct numerical simulation (DNS) and large-eddy simulation (LES) to capture the flow physics. In this study, SBLI is examined for various flow conditions using DNS and LES. -- Abstract.

Download or read book Shock Wave Turbulent Boundary Layer Interaction Over a Protrusion written by Mohammad Ali Badr and published by . This book was released on 2011 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research attempts to investigate an important and common phenomenon in aerodynamics called shock interaction in a turbulent flow's boundary layer. Due to advancements in current computational units, more complex geometries could be simulated with providing more accurate results. The tools used in this investigation are computational turbulent model of hybrid RANS/LES, called detached eddy simulation (DES). DES and its variant delayed detached eddy simulation (DDES) were the two computational schemes used for numerical simulation. Two protrusions were focused on in this work: a symmetrical bump and a proposed aircraft UHF antenna. Computation where performed with commercial software Cobalt and FLUENT in the High Performance Computing Center (HiPeCC) in Wichita State University. Computational simulation is costly in terms of energy consumption and time usage. Even so with the advanced computational units of HiPeCC, using in average of 18 processors, total simulation for this research took over 2 months of simulation.

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.