Necessary Conditions for Transition in a Free Shear Layer.
Abstract
A necessary condition for the preservation of turbulence has been utilized to predict laminar-turbulent transition in free shear, or mixing, layers. Following earlier applications in wakes and boundary layers, the condition is expressed in terms of a threshold turbulence Reynolds number which can be computed if the turbulence properties of the post-transitional flow are known. Assuming that the latter are those reported for self-similar flows, general rules for transition in all major types of shear flows are drawn. Numerical computations are presented for arbitrary homogeneous free shear layer transition identified as the most forward permissible turbulence onset location. Transition is found to move downstream very rapidly as the fast-stream Mach number is increased and the speed ratio is decreased, and less rapidly as the slow stream is heated. Agreement with available transition data is qualitatively good but quantitatively fair, which is ascribed to missing information about the shear layer turbulence and the observed tendency of available transition data to depend on the Reynolds number. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1980
- Accession Number
- ADA085514
Entities
People
- Anthony Demetriades
Organizations
- Montana State University