Accession Number:

ADA242160

Title:

Stability of the Flow Around a Cylinder: The Spin-Up Problem

Descriptive Note:

Contractor rept.

Corporate Author:

INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA

Personal Author(s):

Report Date:

1991-09-01

Pagination or Media Count:

26.0

Abstract:

Our concern is with the flow around an infinite cylinder, which at a certain instant is impulsively started to spin. The growth of vortices in the resulting boundary layer occurring outside the cylinder is investigated. This layer is essentially a Rayleigh layer which grows with time, so the mechanism involved is similar to that studied in Hall 1983. Vortices with wavenumber comparable to the layer thickness are shown to be described by partial differential equations that govern the system numerically. We assume that the Rayleigh layer is thin so particles are confined to move in a path with radius of curvature the same as the cylinder. The Goertler number is a function of time, so we consider the time scale which produces an order one Goertler number. We consider the right hand branch calculation by letting the time tend to infinity. Inviscid Goertler modes are also considered.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE