Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Computation of Three-dimensional Shock Wave and Boundary-layer Interactions
Author: Shock Wave-Boundary-Layer Interactions
Author: Holger BabinskyPublisher: Cambridge University Press
ISBN: 1139498649
Category : Technology & Engineering
Languages : en
Pages : 481
Book Description
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.
Theoretical Investigation of Three-Dimensional Shock Wave Turbulent Boundary Layer Interactions
Author: D. D. KnightPublisher:
ISBN:
Category :
Languages : en
Pages : 52
Book Description
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. This year's principle accomplishments are (1) the Baldwin-Lomax model was evaluated for a series of non-separated two-dimensional turbulent boundary layers. (2) the 3-D Navier-Stokes codes was rewritten innto CYBER 200 FORTRAN. (3) the computed results for the 3-D sharp fin alpha sub g = 10 deg were compared with the results of a separate calculation by C. Horstmann using the k-epsilon turbulence model, and the experimental data of McClure and Dolling. and (4) the 3-D sharp fin at alpha sub g =20 deg was computed, and the results compared with the available experimental data. The examination of the flowfield structure of the 3-D sharp fin at alphaa sub g = 20 deg was initiated. Originator supplied keywords include: High speed flows; Viscous-inviscid interactions; Shock-boundary layer interactions; Computational fluid dynamics; Navier-Stokes equations; and Turbulence.
Theoretical Investigation of Three-Dimensional Shock Wave-Turbulent Boundary Layer Interactions. Part 2
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 71
Book Description
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).
The Structure and Control of Three-Dimensional Shock Wave Turbulent Boundary Layer Interactions
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 30
Book Description
The three year period covered in the subject report was a considerable shift from the previous years of work on shock wave turbulent boundary layer interactions. The earlier work concentrated on simple building block experiments and a search for fundamental understanding of the flow phenomena. In the subject research, most of the work on fundamentals for the simple configurations was stopped. The main emphasis for the first two years of the current program was on complex configurations and the final year was a close-out program on a new approach. The work on complex configurations was limited to two geometries which used the much studied single sharp fin interaction, Fig. 1, as the initial conditions. This shift in emphasis had two main purposes: (1) block experiments in more complex interactions required for applications and (2) to provide a more critical test of computation which, although giving the general characteristics for the building block experiments, did not give highly quantitative results. The primary activities for the first two years will be discussed in three major groupings: (1) and (2) Discussions of the two complex configurations, and (3) a description of the boundary layer conditions which are critical to the definition of the experiment and the check by computational fluid dynamics.
Fluctuations and Massive Separation in Three-Dimensional Shock-Wave/Boundary-Layer Interactions
Author: National Aeronautics and Space Adm NasaPublisher: Independently Published
ISBN: 9781792619748
Category : Science
Languages : en
Pages : 30
Book Description
Shock-wave unsteadiness was observed in rapidly compressed supersonic turbulent boundary layer flows with significant separation. A Mach 2.85 shock-wave/turbulent boundary layer flow was set up over a series of cylinder-flare bodies in the High Reynolds Number Channel 1. The transition from fully attached to fully separated flow was studied using axisymmetric flares with increasing compression angles. In the second phase, the 30 deg flare was inclined relative to the cylinder axis, so that the effect on a separated flow of increasing 3 dimensionality could be observed. Two 3-D separated cases are examined. A simple conditional sampling technique is applied to the data to group them according to an associated shock position. Mean velocities and turbulent kinetic energies, computed from the conditionally samples data, are compared to those from the unsorted data and to computed values. Three basic questions were addressed: can conditional sampling be used to provide snapshots of the flow; are averaged turbulence quantities dominated by the bimodal nature of the interaction; and is the shock unsteadiness really important to computational accuracy. Kussoy, M. I. and Brown, J. D. and Brown, J. L. and Lockman, W. K. and Horstman, C. C. Ames Research Center NASA-TM-89224, NAS 1.15:89224 NCC2-452...
Theoretical Investigation of Three-Dimensional Shock Wave-Turbulent Boundary Layer Interactions. Part 4
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
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.
Theoretical Investigation of Three-Dimensional Shock Wave-Turbulent Boundary Layer Interactions
Author: Doyle D. KnightPublisher:
ISBN:
Category :
Languages : en
Pages : 50
Book Description
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).
Author: Mark J. Rimlinger
Author: