Accession Number : AD0737524

Title :   On Slugs and Puffs in Transitional Pipe Flow.

Descriptive Note : Final rept.,

Corporate Author : BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH

Personal Author(s) : Wygnanski,I. J. ; Champagne,F. H.

Report Date : JAN 1972

Pagination or Media Count : 124

Abstract : Conditionally sampled hot-wire measurements were taken in a pipe at Reynolds numbers corresponding to the onset of turbulence. The pipe was smooth and carefully aligned so that turbulent slugs appeared naturally at a Reynolds number greater than 50,000. Transition could be initiated at lower Reynolds numbers by introducing disturbances into the inlet. For slightly disturbed inlet, turbulent slugs were observed which occupied the entire cross section of the pipe, growing in length as they proceed downstream. When a large distrubance was introduced into the inlet, the turbulent regions which were convected downstream were designated as puffs. Results of the study are discussed.

Descriptors :   (*PIPES, FLUID FLOW), TURBULENCE, TEST METHODS, FLOW FIELDS, REYNOLDS NUMBER, BOUNDARY LAYER TRANSITION

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE