Accession Number:

ADA134796

Title:

Understanding Transition to Turbulence in Shear Layers.

Descriptive Note:

Final rept. 1 Oct 76-31 Dec 82,

Corporate Author:

ILLINOIS INST OF TECH CHICAGO DEPT OF MECHANICS MECHANICAL AND AEROSPACE ENGINEERING

Personal Author(s):

Report Date:

1983-05-01

Pagination or Media Count:

140.0

Abstract:

Critical examination of experimental, analytical and numerical research on shear-flow instabilities evolving into turbulence led to a conceptual framework consistent with reliable observations. Mechanically driven shear layers fall into four classes boundary layers, confined duct flows, free shear layers, and flows in annuli between cylinders driven by the rotation of the inner cylinder. These classes correspond to distinct, initially rather homogeneous vorticity distributions. Each instability restructures these distributions it dehomogenizes them spatially, while the very slow viscous effects smooth the largest gradients. The restructuring continues even after the shear layers become turbulent.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE