Download or read book On Transonic Shock Nonseparating Turbulent Boundary Layer Interaction in Two Dimensional Channels written by A. Kluwick and published by . This book was released on 1976 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow model of Inger and Mason for the interaction of a weak normal shock with a turbulent non-separating boundary layer along a flat plate in an unbounded stream is generalized to the channel flow case. The understanding of such internal flows is highly important not only for the design of turbo-machines but also for comparison of theoretical results obtained under the assumption of an unbounded stream with data resulting from channel flow experiments. The present study deals in particular with the change of the upstream decay rate of the pressure disturbances due to the effect of wave reflections within the channel and the change of the pressure level in this region.
Download or read book Transonic Shock Turbulent Boundary Layer Interaction with Suction and Blowing written by G. R. Inger and published by . This book was released on 1977 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A basic theory of weak normal shock - turbulent boundary layer interactions is given for two-dimensional non-separating flows including mass transfer across the wall throughout the interaction region. Even small amounts of suction are found to significantly reduce both the streamwise scale and thickening effect of the interaction and delay the onset of separation. This is shown to be a consequence of the large mass transfer effect on the shape of the incoming boundary layer Mach number profile away from the wall. Parametric study results showing the influence of Reynolds and shock Mach number as well as mass transfer parameter on the interaction, plus favorable comparisons with various experimental data, are also presented.
Download or read book Some Fundamental Aspects of Shock Wave Turbulent Boundary Interactions in Transonic Flow written by G. R. Inger and published by . This book was released on 1981 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transonic normal shock - turbulent boundary layer interactions can significantly influence not only the local viscous flow but also the downstream behavior of the boundary layer on aerodynamic bodies. It is therefore important that fundamentally-based analytical tools be developed for describing and scaling these interaction effects. This paper examines recent progress toward this goal, with emphasis on two aspects. (1) A basic non-asymptotic triple-deck theory of non-separating two-dimensional interactions that is applicable over a wide range of practical Reynolds numbers and boundary layer profile shapes. (2) Its applicable as a local 'interactive module' in the global transonic flow field analysis of wings, including detailed comparisons with experimental data. Also discussed is the adaptability of this theory to treat interactions involving non-adiabatic wall conditions, including the prediction of incipient separation.
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 Transonic Shock written by George R. Inger and published by . This book was released on 1981 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed analysis is made of weak normal shock-turbulent boundary layer interactions on longitudinally-curved surfaces for the case of non-separating steady 2-D flow. It is shown that the interactive viscous displacement effect on the local outer inviscid transonic flow eliminates the well-known singularity pertaining to a curved wall. The inner interaction solution within the boundary layer reveals that curvature moderately influences the interaction through the turbulent eddy viscosity. A non-asymptotic triple-deck solution valid over a wide range of practical Reynolds numbers is given which incorporates this effect, and example numerical results are presented and verified by comparison with experimental data. Small amounts of curvature are found to moderately spread out and thicken the interaction zone while also delaying slightly the onset of any incipient separation that occurs under the shock. (Author).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1983 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Transonic Shock Turbulent Boundary Layer Interactions on Spinning Axisymmetric Bodies at Zero Angle of Attack written by George R. Inger and published by . This book was released on 1983 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a detailed triple-deck theory of the transonic shock-nonseparating turbulent boundary layer interaction zones on spinning axisymmetric bodies at zero angle of attack. The theory allows a general non-equilibrium turbulent boundary layer history upstream of the interaction. We further describe the application of this theory as a local interactive module imbedded in a global composite viscous-inviscid transonic flow field prediction method which can handle two or more such interaction zones. Detailed comparisons with both experimental data and thin-layer Navier-Stokes code predictions are presented to verify the accuracy and reliability of the composite method solutions for pressure, displacement thickness, velocity profiles, shape factor and skin friction distirbutions along the body over a wide range of Mach/Reynolds number conditions. (Author).
Download or read book Normal Shock Interaction with a Turbulent Boundary Layer on a Curved Wall written by G. R. Inger and published by . This book was released on 1978 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed analysis is made of longitudinal surface curvature effects on the interaction of a weak normal shock with a non-separating two-dimensional turbulent boundary layer. It is shown that the interactive viscous displacement effect on the local outer inviscid transonic flow completely eliminates the well-known singularity pertaining to purely inviscid flow on a curved wall, i.e., the interactive pressure field is regular behind the shock. A study of the inner interaction solution within the boundary layer, however, reveals that curvature can influence the interaction but for a hitherto-overlooked reason: the effect on the turbulent eddy viscosity, which alters the boundary layer profile shape upon which the interaction depends. An approximate nonasymptotic solution is given which incorporates this effect and example numerical results are presented and verified by comparison with experimental data. Small amounts of curvature are found to moderately spread out and thicken the interaction zone while also beneficially delaying the onset of any incipient separation that occurs under the shock foot.
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).
Download or read book Shock Boundary Layer Interaction Effects in Transonic Flow Fields written by G. R. Inger and published by . This book was released on 1980 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the results of a five-year basic theoretical study of non-separating transonic shock-turbulent boundary layer interactions. Both local and downstream boundary layer distortion effects have been studied including extensive comparisons with available experimental data. (Author).
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.
Download or read book Two Dimensional Shock Wave Boundary Layer Interactions in High Speed Flows written by and published by . This book was released on 1975 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review is made of two-dimensional supersonic interactions including separation for laminar and turbulent flows. Part 1 discusses recent theoretical developments in interacting flows and presents numerical techniques for calculating these flows, including finite difference and integral methods. Theoretical discussions are presented for both laminar and turbulent interactions. Part 2 reviews recent experimental studies which have been directed towards understanding the fluid mechanics of attached and separated regions of shock wave-boundary layer interaction in the supersonic and hypersonic flow.
Download or read book Analytical Theory of Transonic Normal Shock Boundary Layer Interaction written by VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG COLL OF ENGINEERING. and published by . This book was released on 1975 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes an approximate analytical theory of the nonseparating transonic interaction of a weak normal shock with an isobaric laminar or turbulent boundary layer. The resulting mixed rotation transonic flow boundary value problem is solved analytically by Fourier transformation methods. Numerical results are presented for turbulent boundary layer pressure distributions, flow geometry and skin friction.
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.
Download or read book Physics of Three dimensional Normal Shock Wave turbulent Boundary Layer Interactions in Rectangular Channels written by Kashmir Sami and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Data from Two Shock Wave Turbulent Boundary Layer Interaction Experiments written by R. J. Vidal and published by . This book was released on 1976 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: The data from two shock wave turbulent boundary layer interaction experiments are compared. In both experiments a normal shock interacted with a two-dimensional turbulent boundary layer in an uniform flow with a Mach number of 1.4. One test was performed in the Ludwieg Tube of Calspan Corporation and the other are in the NLR supersonic blow-down wind tunnel. The general set up of the experiments and the models used were quite similar. The only differences were model dimensions, unit Reynolds number and type of windtunnel. The comparison includes wall pressure, the initial boundary layer and static pressure normal to the plate. The wall pressure distributions of both experiments, scaled with a reference length which is a function of the Reynolds number, correlate very well. There is no indication of any influence of model characteristics on the supersonic part of the pressure distribution. In the NLR experiment the skin friction was calculated with the aid of Clauser plots whereas in the Calspan experiment the skin friction was measured with skin friction transducers. Using one set of data the results of both techniques are compared. (Author).
Download or read book A Normal Shock wave Turbulent Boundary layer Interaction at Transonic Speeds written by George G. Mateer and published by . This book was released on 1976 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
