Global endwall effects on centrifugally stable flows

Marc Avila, Matt Grimes, Juan Lopez, Francisco Marques

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

We investigate the stability of a fluid confined between two cylinders that rotate at same constant angular speed. In the case of infinite cylinders, or endwalls rotating with the cylinders, the flow is in solid-body rotation and hence linearly stable for any rotation speed. However, when the endwalls are stationary, a large-scale circulation is driven by radially inward boundary layer flow on the endwalls. For sufficiently high angular speeds, this circulation becomes unstable to azimuthal waves. As the length-to-gap aspect ratio of the system is increased, a wealth of instabilities is revealed. It is particularly interesting that for all these instabilities the associated energy is localized in the equatorial region, as far from the endwalls as possible. This shows that care must be taken when assuming localized endwall effects in simplified models.

Original languageEnglish (US)
Article number104104
JournalPhysics of Fluids
Volume20
Issue number10
DOIs
StatePublished - 2008

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equatorial regions
boundary layer flow
Boundary layer flow
aspect ratio
Aspect ratio
Fluids
fluids
energy

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Global endwall effects on centrifugally stable flows. / Avila, Marc; Grimes, Matt; Lopez, Juan; Marques, Francisco.

In: Physics of Fluids, Vol. 20, No. 10, 104104, 2008.

Research output: Contribution to journalArticle

Avila, Marc ; Grimes, Matt ; Lopez, Juan ; Marques, Francisco. / Global endwall effects on centrifugally stable flows. In: Physics of Fluids. 2008 ; Vol. 20, No. 10.
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