Author : Laura Lynn Pauley
Publisher :
Page : 222 pages
File Size : 49,3 MB
Release : 1988
Category : Laminar boundary layer
ISBN :
The unsteady, incompressible Navier-Stokes equations were solved using a fractional timestep method. Using this technique, the separation of a laminar boundary layer under the influence of an external adverse pressure gradient was.
Author : Tzuyin Wu
Publisher :
Page : 504 pages
File Size : 13,19 MB
Release : 1991
Category :
ISBN :
Author : David John Gee
Publisher :
Page : 250 pages
File Size : 42,38 MB
Release : 1992
Category :
ISBN :
Author : International Union of Theoretical and Applied Mechanics
Publisher :
Page : 432 pages
File Size : 43,74 MB
Release : 1958
Category : Aerodynamics
ISBN :
Author : Yong Kweon Suh
Publisher :
Page : 116 pages
File Size : 15,91 MB
Release : 1985
Category :
ISBN :
Author : Demetri P. Telionis
Publisher :
Page : 24 pages
File Size : 43,5 MB
Release : 1972
Category : Boundary layer
ISBN :
It has been previously indicated both theoretically and experimentally that for steady flow over moving boundaries, the vanishing of skin friction does not mean separation and that separation occurs at a station where the generalized Moore-Rott-Sears (MRS) criterion is satisfied. The authors have earlier indicated numerically that the Goldstein-type separation-singularity appears at the point where the MRS criterion is satisfied. In the present paper and in accordance with the theoretical work of Sears and one of the authors, this idea is extended to unsteady flows. A Goldstein-type of a traveling singularity is discovered and interpreted as 'unsteady boundary-layer separation.' The features of the flow in the neighborhood of this singularity are investigated. (Author).
Author : Demetri P. Telionis
Publisher :
Page : 24 pages
File Size : 46,79 MB
Release : 1972
Category : Fluid dynamics
ISBN :
Author : T. Cebeci
Publisher :
Page : 19 pages
File Size : 19,23 MB
Release : 1984
Category :
ISBN :
Preliminary results are presented for the analysis of unsteady laminar boundary layers on oscillating airfoils. An examination of the evolution of the boundary layer near the nose of an oscillating airfoil has revealed that, when the reduced frequency is of the same order as in experiments on dynamic stall, the unsteady boundary layer ceases to behave in a smooth manner just downstream of separation and before one cycle is completed. As for the case of the implusively started circular cylinder, the irregular behavior signals the onset of a singularity in the solution of the boundary layer equations. Numerical results for the method are compared with the numerical results of van Dommelen and Shen for the impulsively started circular cylinder, the irregular behavior signals the onset of a singularity in the solution of the boundary layer equations. Numerical results for the method are compared with the numerical results of van Dommelen and Shen for the impulsively started circular cylinder.
Author : James Edward Carter
Publisher :
Page : 72 pages
File Size : 21,30 MB
Release : 1975
Category : Boundary layer
ISBN :
Numerical solutions of the laminar, incompressible boundary-layer equations are presented for flows involving separation and reattachment. Regular solutions are obtained with an inverse approach in which either the displacement thickness or the skin friction is specified; the pressure is deduced from the solution. A vorticity--stream-function formulation of the boundary-layer equations is used to eliminate the unknown pressure. Solutions of the resulting finite-difference equations, in which the flow direction is taken into account, are obtained by several global iteration schemes which are stable and have unconditional diagonal dominance. Results are compared with Klineberg and Steger's separated boundary-layer calculations, and with Briley's solution of the Navier-Stokes equations for a separated region. In addition, an approximate technique is presented in which the streamwise convection of vorticity is set equal to zero in the reversed flow region; such a technique results in a quick forward-marching procedure for separated flows.
Author : Shahram Elli
Publisher :
Page : 134 pages
File Size : 43,8 MB
Release : 1992
Category :
ISBN :
