Nonlinear Aspects of Planar Condensational Instability.

Abstract

Simulate numerically the nonlinear evolution of a radiation driven thermally unstable planar fluid, using a semi-implicit finite difference algorithm. When the equilibrium state of the fluid is perturbed by random initial excitation of the velocity field, dense, cool, two dimensional structures are observed forming in a rarer, warmer, surrounding medium. The nonlinear phase of evolution is characterized by the turbulent contraction of the condensed region, accompanied by a significant increase in the amount of energy radiated. If the random velocity perturbation has a sufficiently large amplitude, the fluid will not form condensed structures. Finally, the relationship of these results to observations of the solar chromosphere, transition region and corona is discussed. Keywords: Instability; Condensation; Solar corona.

Document Details

Document Type
Technical Report
Publication Date
Feb 27, 1987
Accession Number
ADA178998

Entities

People

  • C. R. Devore
  • J. Michael Picone
  • J. T. Karpen
  • J. T. Mariska
  • R. B. Dahlburg

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Algorithms
  • Amplitude
  • Chromosphere
  • Condensation
  • Electromagnetic Radiation
  • Excitation
  • Instability
  • Light (Electromagnetic Radiation)
  • Mathematics
  • Observation
  • Personal Information Managers
  • Radiation
  • Solar Corona
  • Stratified Fluids
  • Transitions
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Plasma Physics / Magnetohydrodynamics
  • Solar Physics