Accession Number:

ADA050755

Title:

The Calculation of Compressible Transitional, Turbulent, and Relaminarizational Boundary Layers over Smooth and Rough Surfaces Using an Extended Mixing-Length Hypothesis

Descriptive Note:

Final rept. Jul 1974-Sep 1977

Corporate Author:

ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN

Personal Author(s):

Report Date:

1978-02-01

Pagination or Media Count:

103.0

Abstract:

Numerical calculations based on the compressible boundary-layer equations and an integral form of the kinetic-energy-of-turbulence IKET equation are presented for a variety of conditions. The addition of the IKET equation permits the streamwise computation of an additional dependent variable normally taken as an empirical constant in conventional mixing-length formulations. A baseline turbulence model is developed and then modified to account for the effects of favorable and adverse pressure gradients, roughness, and transpiration. Examples given include adverse and favorable pressure gradients, relaminarization, acoustic-energy-induced transition, surface roughness, and transpiration. The IKET-based extended mixing-length hypothesis is shown to be considerably more flexible than conventional mixing-length turbulence models.

Subject Categories:

  • Numerical Mathematics
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE