Accession Number : ADA188020

Title :   Wake Interaction Effects on the Transition Process on Turbine Blades.

Descriptive Note : Rept. 1 Sep 86-31 Aug 87,

Corporate Author : OXFORD UNIV (ENGLAND) DEPT OF ENGINEERING SCIENCE

Personal Author(s) : Ainsworth, R W ; LaGraff, J E

PDF Url : ADA188020

Report Date : 30 Oct 1987

Pagination or Media Count : 33

Abstract : The characterisation of the nozzle guide vane inlet and exit conditions in the Oxford University Isentropic Light Piston Tunnel fully 3-D annular rotating stage has been undertaken Measurements included hot wire anemometry and pressure/Mach number distributions. Preparations for the rotor heat transfer instrumentation/data acquisition hardware and software are also in progress. Further development of a numerical model to predict the effects of wake passing and transition is reported. The convection of the wake through the passage is predicted, allowing for estimations of the expected times for which the boundary layer is disturbed by the wake fluid. The new model for the random generation and subsequent growth and convection of the turbulent spots produces a time-resolved prediction of the intermittent heat transfer signals by use of a time-marching procedure. By superimposing the two numerical models it is possible to simulate the measured instantaneous heat transfer characteristics and to estimate the effective average intermittency along the blade surface and compare the results to the measured intermittency values.

Descriptors :   *BOUNDARY LAYER TRANSITION, *HEAT TRANSFER, *GAS TURBINE BLADES, *WAKE, COMPUTER PROGRAMS, ESTIMATES, EXITS, FLUIDS, GUIDE VANES, HOT WIRE ANEMOMETERS, INLETS, INTERACTIONS, MACH NUMBER, MATHEMATICAL MODELS, GAS TURBINE NOZZLES, MATHEMATICAL PREDICTION, PREPARATION, PRESSURE DISTRIBUTION, SIGNALS, SURFACES, TIME, TRANSITIONS, TURBULENCE, INLET GUIDE VANES, SKIN FRICTION, AEROTHERMODYNAMICS, GAS TURBINE ROTORS, GREAT BRITAIN

Subject Categories : Fluid Mechanics
      Jet and Gas Turbine Engines
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE