Accession Number : ADA335279

Title :   The Interaction of Shear Flows Generated by a Surface-Piercing Splitter Plate w/Free Surface

Descriptive Note : Final rept. 1 Oct 93-14 Sep 96

Corporate Author : CALIFORNIA INST OF TECH PASADENA DEPT OF AERONAUTICS

Personal Author(s) : Gharib, Mory ; Valluri, Sid ; Roshko, Anatol

PDF Url : ADA335279

Report Date : 26 NOV 1997

Pagination or Media Count : 79

Abstract : An experimental study is performed in a water tunnel (Re = 40,000 to Re = 60,000) to study the interaction between the wake of a circular disk and the free surface. The deformation of the free surface is correlated with the behavior of the wake by utilizing surface pictures, wake flow visualization, drag measurement and Digital Particle Image Velocimetry techniques. It is observed that the wake can exist in two modes with different stabilities. The flow can switch between these two modes and the switching process exhibits hysteresis. The topological differences between these modes and their relation to the observed surface patterns are discussed. The changes in the wake are reflected by an increase in Cd which reaches a maximum value when the upper edge of the disk is 0.125 diameters from the surface. Comparison is also made with a disk approaching a solid boundary.

Descriptors :   *WAKE, *SHEAR FLOW, DEFORMATION, TURBULENT FLOW, COMPUTATIONAL FLUID DYNAMICS, FLOW VISUALIZATION, FLOW FIELDS, DRAG, FLOW SEPARATION, REYNOLDS NUMBER, LASER VELOCIMETERS, WATER TUNNELS, STAGNATION POINT.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE