Accession Number : ADA312457

Title :   Aero-Thermal Cascade Tunnel Flow Quality: Turbulence Generation and Prediction.

Descriptive Note : Final rept. 1 Nov 95-9 Jul 96,

Corporate Author : WRIGHT LAB WRIGHT-PATTERSON AFB OH

Personal Author(s) : Duncan, John ; Petersen, Kristin

PDF Url : ADA312457

Report Date : 29 NOV 1995

Pagination or Media Count : 94

Abstract : Turbine blade temperatures in modern turbine engines are the limiting factor in the advancement of aircraft propulsion today. One reason for the blades' thermal stress failure has to do with the traverse effects of turbulent flow over the blades--the more turbulence in the flow, the greater the heat transfer to the blade. Of concern here are both freestream and boundary layer turbulence. Therefore, the focus of much research today is on studying turbine blade models with post-burner turbulent flow conditions in order to design and build blades around the predicted failure levels and coordinates. The focus of this paper is on the generation of the turbulence characteristics which will be necessary for use in cascade wind tunnel facilities. Methods of turbulence generation and turbulence trends are analyzed with the main parameter being turbulence intensity variation with both lateral and streamwise location. The results presented here are a complete turbulent flow field description for a turbulence generation method, supporting the 'air off' grid configuration as ready for use and research while demanding revision of the 'air on' high turbulence generation method.

Descriptors :   *HEAT TRANSFER, *TURBULENT FLOW, *GAS TURBINE BLADES, AIR FLOW, TURBULENCE, EDDIES(FLUID MECHANICS), TURBULENT BOUNDARY LAYER, VORTICES, COMPUTATIONAL FLUID DYNAMICS, GAS TURBINES, FLOW FIELDS, TEMPERATURE GRADIENTS, WIND TUNNEL TESTS, AEROTHERMODYNAMICS, FREE STREAM, SURFACE TEMPERATURE, PRESSURE DISTRIBUTION, REYNOLDS NUMBER, THERMAL STRESSES, BOUNDARY LAYER FLOW, HEAT TRANSFER COEFFICIENTS, CASCADES(FLUID DYNAMICS).

Subject Categories : Fluid Mechanics
      Thermodynamics
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE