Accession Number:

ADA250606

Title:

Unsteady and Separated Flows

Descriptive Note:

Final rept. 1 Oct 1986-10 Nov 1991

Corporate Author:

CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS

Report Date:

1992-04-10

Pagination or Media Count:

191.0

Abstract:

In these investigations, simple geometries were studied. Experiments and simulations examined the addition of unsteady motions, of flat plates inclined normal to the flow, and circular cylinders, to the conventional-steady motions of these bodies. The simulations also investigated the three-dimensional interactions of vortex rings and the startup flow of a square flat plate oriented normal to the direction of motion bluff body configuration. Laboratory experiments and measurements on flow past flat plates nominally normal to the direction of motion were performed. The objectives of this research were to elucidate the dynamics of large vortical structure in globally steady and unsteady separated flows, and to develop techniques to modify their behavior and control them for desired effect. In-line accelerations and transverse oscillations of flat plates were evaluated to modify the flow structure. These investigations examined the behavior of the large vortical structures in the resulting unsteady and separated flow, and the associated forces on the flat plate. Vortex methods were used to study two- and three-dimensional flows. The objectives of this research were to develop methods to examine the large-scale separated vortices in the wake of bluff bodies, study the influence of transient motions of the body on these dynamics, and investigate control strategies to produce desired effects.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE