Accession Number : ADP005904

Title :   Some Visualization Studies on Turbulent Boundary Layers Using Multiwire Hydrogen Bubble Generation,

Corporate Author : TECHNISCHE HOGESCHOOL EINDHOVEN (NETHERLANDS)

Personal Author(s) : Blokland, R. ; Prasad, K. K.

Report Date : JUN 1987

Pagination or Media Count : 12

Abstract : This report provides some new results obtained with two visualization methods that assist in describing essentially three dimensional phenomena: 1) With two wire certain structure; 2) Multiple colour illumination allows recognition of movements in a direction normal to the plane of the photograph from changes in colour. Some countings were made concerning the behaviour of low speed streaks as a function of y and the relation between streaks and some other structures. A new detection criterion for streaks in proposed. The distribution for the spanwise velocity of a streak was determined. It is shown that the detection criterion of Blackwelder and Kaplan essentially samples spanwise passages of streaks. A few results of multiple colour visualization are shown to establish unambiguously the vertical transport associated with streaks.

Descriptors :   *FLOW VISUALIZATION, *TURBULENT BOUNDARY LAYER, WATER FLOW, THREE DIMENSIONAL, BUBBLES, HYDROGEN, TRANSPORT PROPERTIES, WIRE, PATTERNS, PATTERNS, CORRELATION, COLOR PHOTOGRAPHY, FLOW FIELDS, LOW VELOCITY, NETHERLANDS.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE