Stability of Self-Similar Flow. 6. Uniform Implosion of an Ablatively Driven Shell.
Abstract
The linear stability of a uniformly imploding shell, modeled as an ideal polytropic fluid, is investigated. Two types of unstable modes are found: incompressible irrotational perturbations localized at the outer surface, ascribable to Rayleigh-Taylor instability, and compressible modes, associated with convective instability. KIDDER'S (1976) result for the Rayleigh-Taylor modes is shown to hold independently of the form of the shell density profile. By means of a variational principle it is shown that the criterion for convective instability is the existence of a region within which the differential of p times rho to the negative gamma power in respect to r>0. Analytic solutions for both spatial and temporal dependence of the perturbations are presented, and the results applied to pellets imploded by the action of a laser or charged-particle beam. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 17, 1979
- Accession Number
- ADA079890
Entities
People
- David L. Book
- Ira B. Bernstein
Organizations
- United States Naval Research Laboratory