Author: P. Hall
Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
On Nonlinear Tollmien-Schlichting/vortex Interaction in Three Dimensional Boundary Layers
Author: Dominic A. R. Davis
Publisher:
ISBN:
Category : Eddies
Languages : en
Pages : 32
Book Description
Publisher:
ISBN:
Category : Eddies
Languages : en
Pages : 32
Book Description
On Nonlinear Tollmien-Schlichting/Vortex Interaction in Three-Dimensional Boundary Layers
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722451806
Category :
Languages : en
Pages : 30
Book Description
The instability of an incompressible three-dimensional boundary layer (that is, one with cross-flow) is considered theoretically and computationally in the context of vortex/wave interactions. Specifically the work centers on two low amplitude, lower-branch Tollmien-Schlichting waves which mutually interact to induce a weak longitudinal vortex flow; the vortex motion, in turn, gives rise to significant wave-modulation via wall-shear forcing. The characteristic Reynolds number is taken as a large parameter and, as a consequence, the waves' and the vortex motion are governed primarily by triple-deck theory. The nonlinear interaction is captured by a viscous partial-differential system for the vortex coupled with a pair of amplitude equations for each wave pressure. Three distinct possibilities were found to emerge for the nonlinear behavior of the flow solution downstream - an algebraic finite-distance singularity, far downstream saturation or far-downstream wave-decay (leaving pure vortex flow) - depending on the input conditions, the wave angles, and the size of the cross-flow. Davis, Dominic A. R. and Smith, Frank T. Glenn Research Center NCC3-233; RTOP 505-62-21...
Publisher: Createspace Independent Publishing Platform
ISBN: 9781722451806
Category :
Languages : en
Pages : 30
Book Description
The instability of an incompressible three-dimensional boundary layer (that is, one with cross-flow) is considered theoretically and computationally in the context of vortex/wave interactions. Specifically the work centers on two low amplitude, lower-branch Tollmien-Schlichting waves which mutually interact to induce a weak longitudinal vortex flow; the vortex motion, in turn, gives rise to significant wave-modulation via wall-shear forcing. The characteristic Reynolds number is taken as a large parameter and, as a consequence, the waves' and the vortex motion are governed primarily by triple-deck theory. The nonlinear interaction is captured by a viscous partial-differential system for the vortex coupled with a pair of amplitude equations for each wave pressure. Three distinct possibilities were found to emerge for the nonlinear behavior of the flow solution downstream - an algebraic finite-distance singularity, far downstream saturation or far-downstream wave-decay (leaving pure vortex flow) - depending on the input conditions, the wave angles, and the size of the cross-flow. Davis, Dominic A. R. and Smith, Frank T. Glenn Research Center NCC3-233; RTOP 505-62-21...
IUTAM Symposium on Nonlinear Instability and Transition in Three-Dimensional Boundary Layers
Author: Peter W. Duck
Publisher: Springer Science & Business Media
ISBN: 9400917007
Category : Science
Languages : en
Pages : 458
Book Description
Most fluid flows of practical importance are fully three-dimensional, so the non-linear instability properties of three-dimensional flows are of particular interest. In some cases the three-dimensionality may have been caused by a finite amplitude disturbance whilst, more usually, the unperturbed state is three-dimensional. Practical applications where transition is thought to be associated with non-linearity in a three- dimensional flow arise, for example, in aerodynamics (swept wings, engine nacelles, etc.), turbines and aortic blood flow. Here inviscid `cross-flow' disturbances as well as Tollmien-Schlichting and Görtler vortices can all occur simultaneously and their mutual non-linear behaviour must be understood if transition is to be predicted. The non-linear interactions are so complex that usually fully numerical or combined asymptotic/numerical methods must be used. Moreover, in view of the complexity of the instability processes, there is also a growing need for detailed and accurate experimental information. Carefully conducted tests allow us to identify those elements of a particular problem which are dominant. This assists in both the formulation of a relevant theoretical problem and the subsequent physical validation of predictions. It should be noted that the demands made upon the skills of the experimentalist are high and that the tests can be extremely sophisticated - often making use of the latest developments in flow diagnostic techniques, automated high speed data gathering, data analysis, fast processing and presentation.
Publisher: Springer Science & Business Media
ISBN: 9400917007
Category : Science
Languages : en
Pages : 458
Book Description
Most fluid flows of practical importance are fully three-dimensional, so the non-linear instability properties of three-dimensional flows are of particular interest. In some cases the three-dimensionality may have been caused by a finite amplitude disturbance whilst, more usually, the unperturbed state is three-dimensional. Practical applications where transition is thought to be associated with non-linearity in a three- dimensional flow arise, for example, in aerodynamics (swept wings, engine nacelles, etc.), turbines and aortic blood flow. Here inviscid `cross-flow' disturbances as well as Tollmien-Schlichting and Görtler vortices can all occur simultaneously and their mutual non-linear behaviour must be understood if transition is to be predicted. The non-linear interactions are so complex that usually fully numerical or combined asymptotic/numerical methods must be used. Moreover, in view of the complexity of the instability processes, there is also a growing need for detailed and accurate experimental information. Carefully conducted tests allow us to identify those elements of a particular problem which are dominant. This assists in both the formulation of a relevant theoretical problem and the subsequent physical validation of predictions. It should be noted that the demands made upon the skills of the experimentalist are high and that the tests can be extremely sophisticated - often making use of the latest developments in flow diagnostic techniques, automated high speed data gathering, data analysis, fast processing and presentation.
Recent Advances in Boundary Layer Theory
Author: Alfred Kluwick
Publisher: Springer
ISBN: 3709125189
Category : Science
Languages : en
Pages : 336
Book Description
Recent advances in boundary-layer theory have shown how modern analytical and computational techniques can and should be combined to deepen the understanding of high Reynolds number flows and to design effective calculation strategies. This is the unifying theme of the present volume which addresses laminar as well as turbulent flows.
Publisher: Springer
ISBN: 3709125189
Category : Science
Languages : en
Pages : 336
Book Description
Recent advances in boundary-layer theory have shown how modern analytical and computational techniques can and should be combined to deepen the understanding of high Reynolds number flows and to design effective calculation strategies. This is the unifying theme of the present volume which addresses laminar as well as turbulent flows.
Nonlinear Interaction of Near-planar TS Waves and Longitudinal Vortices in Boundary-layer Transition
Author: Institute for Computer Applications in Science and Engineering
Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
Viscous Drag Reduction in Boundary Layers
Author:
Publisher: AIAA
ISBN: 9781600863783
Category : Boundary layer
Languages : en
Pages : 542
Book Description
Publisher: AIAA
ISBN: 9781600863783
Category : Boundary layer
Languages : en
Pages : 542
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 892
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 892
Book Description
NASA Technical Paper
Author: United States. National Aeronautics and Space Administration
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 56
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 56
Book Description
On the Initial Stages of Vortex Wave Interactions in Highly Curved Boundary Layer Flows
Author: Philip Hall
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 40
Book Description
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 40
Book Description
NASA Technical Paper
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 56
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 56
Book Description