Linear Stability of Self-Similar Flow: 5. Convective Instability in Bounded Uniform Self-Gravitating Spheres.

Abstract

A new type of instability, similar to thermal convective instabilities, has been found to occur in self-gravitating spherical clouds uniformily expanding or collapsing in a vacuum. Unlike the Jeans instability, it has a growth rate which increases with zonal mode number 1, so that objects of arbitrarily small size are unstable. The modes are compressional and have non-vanishing vorticity. The eigenfunctions peak at the boundary, so the perturbations develop predominantly into surface irregularities. The perturbation amplitudes grow algebraically at first, then at late times become proportional to the cloud radius R(t). For a collapsing system in which stars are produced by the condensation of diffuse matter the theory predicts fragmentation and enhanced condensation in the peripheral regions. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jun 06, 1979
Accession Number
ADA070709

Entities

People

  • David L. Book
  • Ira B. Bernstein

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Amplification
  • Amplitude
  • Boundaries
  • Condensation
  • Equations
  • Instability
  • Long Wavelengths
  • Military Research
  • Perturbations
  • Rayleigh Taylor Instability
  • Security
  • Short Wavelengths
  • Specific Heat
  • Standing Waves
  • Stellar Evolution
  • Stratified Fluids
  • Time Dependence

Fields of Study

  • Physics

Readers

  • Astronomy/Astrophysics
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.