Adiabatic heating of contracting turbulent fluids

Brant E Robertson, Peter Goldreich

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Turbulence influences the behavior of many astrophysical systems, frequently by providing non-thermal pressure support through random bulk motions. Although turbulence is commonly studied in systems with constant volume and mean density, turbulent astrophysical gases often expand or contract under the influence of pressure or gravity. Here, we examine the behavior of turbulence in contracting volumes using idealized models of compressed gases. Employing numerical simulations and an analytical model, we identify a simple mechanism by which the turbulent motions of contracting gases "adiabatically heat," experiencing an increase in their random bulk velocities until the largest eddies in the gas circulate over a Hubble time of the contraction. Adiabatic heating provides a mechanism for sustaining turbulence in gases where no large-scale driving exists. We describe this mechanism in detail and discuss some potential applications to turbulence in astrophysical settings.

Original languageEnglish (US)
Article numberL13
JournalAstrophysical Journal Letters
Volume750
Issue number2
DOIs
StatePublished - May 10 2012

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turbulence
heating
fluid
fluids
astrophysics
gas
gases
compressed gas
sustaining
contraction
eddy
vortices
gravity
gravitation
heat
simulation

Keywords

  • hydrodynamics
  • turbulence

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Adiabatic heating of contracting turbulent fluids. / Robertson, Brant E; Goldreich, Peter.

In: Astrophysical Journal Letters, Vol. 750, No. 2, L13, 10.05.2012.

Research output: Contribution to journalArticle

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