Accession Number : ADA304396

Title :   Turbulent Spot Generation and Growth Rates in a Compressible Boundary Layer.

Descriptive Note : Final rept. 15 Dec 91-31 Aug 95,

Corporate Author : SYRACUSE UNIV NY

Personal Author(s) : LaGraff, John E. ; Jones, Terry V.

PDF Url : ADA304396

Report Date : OCT 1995

Pagination or Media Count : 17

Abstract : Experimental tests were conducted to examine the behavior of naturally occurring turbulent spots over a wide range of gas-turbine representative conditions including: subsonic and supersonic flow, acceleration parameters, and freestream turbulence intensities. Turbulent spot propagation velocities, spreading angles, generation rates, and overhang profiles were determined using high-frequency data acquisition equipment in combination with high-density thin-film technology and hot wire anemometry. A new theory for the influence of the turbulent spot disturbance on a laminar boundary layer has been developed and supported with experimental and computational data. Modelling of the transition zone intermittency using spot characteristics was conducted using a new Dynamic Spot Model.

Descriptors :   *BOUNDARY LAYER, *TURBULENCE, *GAS TURBINES, *TRANSITIONS, VELOCITY, PROPAGATION, EXPERIMENTAL DATA, COMPUTATIONS, MODELS, DYNAMICS, PARAMETERS, EXPERIMENTAL DESIGN, ACCELERATION, GROWTH(GENERAL), THEORY, THIN FILMS, INTENSITY, RATES, TEST METHODS, HIGH DENSITY, SUBSONIC FLOW, RANGE(EXTREMES), SUPERSONIC FLOW, FREE STREAM, HOT WIRE ANEMOMETERS, COMPRESSIVE PROPERTIES.

Subject Categories : Fluid Mechanics
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE