EFFECT OF FREE-STREAM VORTICITY ON BOUNDARY-LAYER STABILITY

The Orr-Sommerfeld equation was used to ascertain the influence of free-stream vorticity on the stability of incompressible boundary-layer flow. The primary flow velocity profiles were obtained using second-order boundary- layer theory. Self-similar flows with positive and negative pressure gradients and free-stream vorticities were considered. The results show how positive vorticity at the edge of the boundary layer is stabilizing and how the free- stream vorticity influences the critical Reynolds numbers more when the pressure gradient is small, and the range of unstable wave lengths more when the pressure gradient is large. The present results indicate that small amounts of vorticity in the free stream might have a large influence on transition.

• Corporate Authors:

  Virginia Polytechnic Institute and State University, Blacksburg

  Department of Agronomy
  Blacksburg, VA  United States  24061
• Authors:
  • Werle, M J
  • Mook, D T
  • Tang, Hongwu
• Publication Date: 1972-2

Media Info

• Pagination: 38 p.

Subject/Index Terms

• TRT Terms: Boundary layer; Velocity; Vortices
• Old TRIS Terms: Boundary layer stability; Boundary layer theory; Velocity profiles
• Subject Areas: Design; Marine Transportation;

Filing Info

• Accession Number: 00035620
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: VPI-E-72-2 Final Rpt
• Contract Numbers: NSF-GK-5224
• Files: TRIS
• Created Date: Oct 27 1972 12:00AM