Accession Number:

ADA070043

Title:

Vorticity-Stream Function Formulation of Compressible and Incompressible Turbulent Internal Flows

Descriptive Note:

Final rept. Sep 1977-Sep 1978

Corporate Author:

ARO INC ARNOLD AFS TN

Personal Author(s):

Report Date:

1979-05-01

Pagination or Media Count:

28.0

Abstract:

Ducted turbulent flows with varying wall shapes are formulated with the Navier-Stokes equations written in terms of vorticity and stream function. Coordinate transformation and stretching functions are used to provide adequate resolution throughout the whole flow field. The turbulent characteristics of the flow are modeled by a low Reynolds number, two-equation k-epsilon model which is applicable in the wall sublayer as well as in the region away from the wall. In addition to the conventional Poisson-type pressure equation, a new pressure equation with both first- and second-order terms was derived from the momentum equations. A vector path function is included in the pressure equation to improve convergence and accuracy. Applications to a model wind tunnel diffuser and a sudden expansion diffuser are discussed. Good agreement with available experimental data is observed in terms of the pressure coefficient and the length of the recirculation region.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE