Three-dimensional instabilities in a discretely heated annular flow

Onset of spatio-temporal complexity via defect dynamics

Juan Lopez, Francisco Marques

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The transition to three-dimensional and unsteady flow in an annulus with a discrete heat source on the inner cylinder is studied numerically. For large applied heat flux through the heater (large Grashof number Gr), there is a strong wall plume originating at the heater that reaches the top and forms a large scale axisymmetric wavy structure along the top. For Gr≈6×109, this wavy structure becomes unstable to three-dimensional instabilities with high azimuthal wavenumbers m ~ 30, influenced by mode competition within an Eckhaus band of wavenumbers. Coexisting with some of these steady three-dimensional states, solution branches with localized defects break parity and result in spatio-temporal dynamics. We have identified two such time dependent states. One is a limit cycle that while breaking spatial parity, retains spatio-temporal parity. The other branch corresponds to quasi-periodic states that have globally broken parity.

Original languageEnglish (US)
Article number064102
JournalPhysics of Fluids
Volume26
Issue number6
DOIs
StatePublished - Jun 10 2014

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annular flow
Grashof number
Unsteady flow
Engine cylinders
Heat flux
parity
Defects
defects
heaters
three dimensional flow
unsteady flow
annuli
heat sources
plumes
heat flux
cycles
Hot Temperature

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Three-dimensional instabilities in a discretely heated annular flow : Onset of spatio-temporal complexity via defect dynamics. / Lopez, Juan; Marques, Francisco.

In: Physics of Fluids, Vol. 26, No. 6, 064102, 10.06.2014.

Research output: Contribution to journalArticle

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