Accession Number:

ADA273470

Title:

Heat Transfer and Flow Structure in End-Wall Boundary Layers

Descriptive Note:

Final rept. 15 Mar 1991-15 Mar 1993

Corporate Author:

LEHIGH UNIV BETHLEHEM PA DEPT OF MECHANICAL ENGINEERING AND MECHANICS

Personal Author(s):

Report Date:

1993-08-11

Pagination or Media Count:

29.0

Abstract:

Research progress is described for a combined analyticalexperimental program examining the flow structure and resultant surface heat transfer in end- wall boundary layers e.g. wing-body. type junctures. Emphasis is placed on flow structure development and correlation of vortex-induced surface interactions with transient, local surface heat transfer. Analytically, numerical studies using an impulsively-started approach flow have documented the flow development and surface heat transfer on the symmetry plane for several end-wall flows highly unsteady vortex formation and ejection are observed, with concomitant sharp, transient variations in surface heat transfer. Analysis of the complete three-dimensional behavior indicates the presence of strong interactions between the end-wall surface and the side-wall bluff-body boundary layers. Experimentally, a constant heat flux test system has been developed and instrumented for surface temperature detection using temperature- sensitive liquid crystals and color computer-image analysis tests indicate dramatic effects of transient end-wall vortices on surface heat transfer, confirming the analytical results. A systematic visualization study indicates a very strong influence of the junction-induced pressure gradient on the approach boundary layer in promoting the unsteady vortex formation processes in the end- wall region. Three-dimensional, Vortex motion, Heat transfer, End-wall flows, Turbulent boundary layers, Fluid mechanics.

Subject Categories:

  • Fluid Mechanics
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE