Author: D. I. A. Poll
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The Effect of Wing Sweep Back Upon Transition in Hypersonic Flow
Author: D. I. A. Poll
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Some Effects of Leading-edge Sweep on Boundary-layer Transition at Supersonic Speeds
Author: Gary T. Chapman
Publisher:
ISBN:
Category :
Languages : en
Pages : 1
Book Description
The effects of crossflow and shock strength on transition of the laminar boundary layer behind a swept leading edge have been investigated analytically and with the aid of available experimental data. An approximate method of determining the crossflow Reynolds number on a leading edge of circular cross section at supersonic speeds is presented. The applicability of the critical crossflow criterion described by Owen and Randall for transition on swept wings in subsonic flow was examined for the case of supersonic flow over swept circular cylinders. A wide range of applicability of the subsonic critical values is indicated. The corresponding magnitude of crossflow velocity necessary to cause instability on the surface of a swept wing at supersonic speeds was also calculated and found to be small. The effects of shock strength on transition caused by Tollmien-Schlichting type of instability are discussed briefly. Changes in local Reynolds number, due to shock strength, were found analytically to have considerably more effect on transition caused by Tollmien-Schlichting instability than on transition caused by crossflow instability. Changes in the mechanism controlling transition from Tollmien-Schlichting instability to crossflow instability were found to be possible as a wing is swept back and to result in large reductions in the length of laminar flow. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 1
Book Description
The effects of crossflow and shock strength on transition of the laminar boundary layer behind a swept leading edge have been investigated analytically and with the aid of available experimental data. An approximate method of determining the crossflow Reynolds number on a leading edge of circular cross section at supersonic speeds is presented. The applicability of the critical crossflow criterion described by Owen and Randall for transition on swept wings in subsonic flow was examined for the case of supersonic flow over swept circular cylinders. A wide range of applicability of the subsonic critical values is indicated. The corresponding magnitude of crossflow velocity necessary to cause instability on the surface of a swept wing at supersonic speeds was also calculated and found to be small. The effects of shock strength on transition caused by Tollmien-Schlichting type of instability are discussed briefly. Changes in local Reynolds number, due to shock strength, were found analytically to have considerably more effect on transition caused by Tollmien-Schlichting instability than on transition caused by crossflow instability. Changes in the mechanism controlling transition from Tollmien-Schlichting instability to crossflow instability were found to be possible as a wing is swept back and to result in large reductions in the length of laminar flow. (Author).
Some Effects of Leading-edge Sweep on Boundary-layer Transition at Supersonic Speeds
Author: Gary T. Chapman
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 38
Book Description
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 38
Book Description
NASA Technical Note
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 260
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 260
Book Description
Effects of Wing Sweep on Boundary-layer Transition for a Smooth F-14A Wing at Mach Numbers from 0.700 to 0.825
Author: Bianca Trujillo Anderson
Publisher:
ISBN:
Category : Laminar flow
Languages : en
Pages : 0
Book Description
Publisher:
ISBN:
Category : Laminar flow
Languages : en
Pages : 0
Book Description
Comments on Hypersonic Boundary-layer Transition
Author: Kenneth F. Stetson
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 116
Book Description
This is a survey paper on the subject of hypersonic boundary-layer transition. Part 1 discusses boundary-layer stability theory, hypersonic boundary-layer stability experiments, and a comparison between theory and experiment. Part 2 contains comments on how many configuration and flow parameters influence transition. Part 3 discusses some additional general aspects of transition. Part 4 discusses problems of predicting transition and comments on three prediction methods. Part 5 contains some general guidelines for prediction methodology. Keywords: Boundary layer transition, Boundary layer stability, Hypersonic boundary layers.
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 116
Book Description
This is a survey paper on the subject of hypersonic boundary-layer transition. Part 1 discusses boundary-layer stability theory, hypersonic boundary-layer stability experiments, and a comparison between theory and experiment. Part 2 contains comments on how many configuration and flow parameters influence transition. Part 3 discusses some additional general aspects of transition. Part 4 discusses problems of predicting transition and comments on three prediction methods. Part 5 contains some general guidelines for prediction methodology. Keywords: Boundary layer transition, Boundary layer stability, Hypersonic boundary layers.
International Aerospace Abstracts
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 962
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 962
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
On the Hypersonic Flow Over a Delta Wing with Very Supersonic Leading Edges
Author: Norman D. Malmuth
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 66
Book Description
For the case of very supersonic leading edges, the inviscid hypersonic flow over the windward side of a symmetrical flat-plate delta wing at incidence is analyzed. The limit selected is that the incidence is of higher order than the aspect ratio as the incidence tends to zero at infinite Mach number. In this framework, the flow regions consist of a two-dimensional domain adjacent to the leading edges and a central conefield. The flow quantities in the central region represent small linear, rotational perturbations about the zero sweep flow. A Riemann-Poincare boundary value problem for the pressure perturbation is formulated. An additional condition involving the sidewash at the shock is found to be required to resolve the indeterminacy of the foregoing boundary value problem. Series solutions and numerical results are presented for the shock shape and the pressure. The behavior of the latter quantity is found to be similar to that given by the irrotational linear solution for the supersonic leading edge case. Finally, the relationship between the present application and others involving diffraction problems and corner flows is indicated.
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 66
Book Description
For the case of very supersonic leading edges, the inviscid hypersonic flow over the windward side of a symmetrical flat-plate delta wing at incidence is analyzed. The limit selected is that the incidence is of higher order than the aspect ratio as the incidence tends to zero at infinite Mach number. In this framework, the flow regions consist of a two-dimensional domain adjacent to the leading edges and a central conefield. The flow quantities in the central region represent small linear, rotational perturbations about the zero sweep flow. A Riemann-Poincare boundary value problem for the pressure perturbation is formulated. An additional condition involving the sidewash at the shock is found to be required to resolve the indeterminacy of the foregoing boundary value problem. Series solutions and numerical results are presented for the shock shape and the pressure. The behavior of the latter quantity is found to be similar to that given by the irrotational linear solution for the supersonic leading edge case. Finally, the relationship between the present application and others involving diffraction problems and corner flows is indicated.
The Calculation of Downwash Behind Supersonic Wings with an Application to Triangular Plan Forms
Author: Maxwell Alfred Heaslet
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 52
Book Description
A method is developed, consistent with the assumptions of small perturbation theory, which provides a means of determining for a known load distribution, the downwash behind a wing in supersonic flow. THe analysis is based upon the use of supersonic doublets which are distributed over the plan form and wake of the wing in a manner determined from the wing loading.
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 52
Book Description
A method is developed, consistent with the assumptions of small perturbation theory, which provides a means of determining for a known load distribution, the downwash behind a wing in supersonic flow. THe analysis is based upon the use of supersonic doublets which are distributed over the plan form and wake of the wing in a manner determined from the wing loading.