Viscous Effects in Rayleigh-Taylor Instability.

Abstract

A simple, physical approximation is developed for the effect of viscosity for stable interfacial waves and for the unstable interfacial waves which correspond to Rayleigh-Taylor instability. The approximate picture is rigorously justified for the interface between a heavy fluid (e.g., water) and a light fluid (e.g., air) with negligible dynamic effect. The approximate picture may also be rigorously justified for the case of two fluids for which the differences in density and viscosity are small. The treatment of the interfacial waves may be easily extended to the case where one of the fluids has a small thickness; that is, when one of the fluids is bounded by a free surface or by a rigid wall. The theory is used to give an explanation of the bioconvective patterns which have been observed with cultures of micro-organisms which have negative geotaxis. Since such organisms tend to collect at the surface of a culture and since they are heavier than water, the conditions for Rayleigh-Taylor instability are met. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1973
Accession Number
AD0764119

Entities

People

  • Christopher G. Whipple
  • Milton S. Plesset

Organizations

  • California Institute of Technology

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Instability
  • Physical Properties
  • Rayleigh Taylor Instability
  • Thickness
  • Viscosity

Fields of Study

  • Mathematics

Readers

  • Fluid Dynamics.
  • Marine Ecotoxicology