Accession Number : AD0679234

Title :   THE INTERMITTENTLY TURBULENT REGION OF THE BOUNDARY LAYER.

Descriptive Note : Interim rept.,

Corporate Author : UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF AEROSPACE ENGINEERING

Personal Author(s) : Kaplan,Richard E. ; Laufer,John

Report Date : NOV 1968

Pagination or Media Count : 30

Abstract : Measurements were made in the region of the turbulent boundary layer where the flow state alternates between turbulent and non-turbulent. The emphasis of the experiment was to explore the technique of using arrays of hot wire anemometers and analyzing the signals of these wires with a digital computer. A technique similar to the one used is necessary to determine statistics of the intermittent flow more sophisticated than the conventional and familiar intermittency distribution. Techniques and criteria for forming a broader class of 'ensemble' averages for intermittent flows are discussed. In particular, emphasis is placed on the concept of 'conditional' averages of pertinent physical variables in this type of flow. Useful examples of this type of average are the average velocity distribution in the turbulent region, and velocity distributions related to a specified position of the interface between the turbulent and non-turbulent fluid. (Author)

Descriptors :   (*TURBULENT BOUNDARY LAYER, INTERFACES), DATA PROCESSING, DETECTORS, BOUNDARY LAYER TRANSITION, SAMPLING, LAMINAR FLOW, DIGITAL COMPUTERS, VELOCITY, DISTRIBUTION

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE