A Variational Approach to the Rayleigh-Taylor Instability of an Accelerating Plasma Slab.
Abstract
The growth rate of the hydromagnetic Rayleigh-Taylor instability is approximated here for an accelerating plasma slab. The slab is chosen as a large-radius approximation to an imploding cylindrical foil. A normal mode solution of the MHD equations is assumed, resulting in an integral relation for the instability growth rate. The Rayleigh-Ritz variational method is applied to the relation to estimate the growth rate. A linearly decreasing magnetic field is assumed in the slab perpendicular to the acceleration. A corresponding equilibrium mass density profile is then found. Growth rate estimates are then made for these profiles. Calculations are made for perturbation wavevectors perpendicular to the acceleration and at an angle theta to the magnetic field. The growth rates for theta = 90 degrees compare favorably with LeLevier et al's results for a continuous density transition (14). Growth rates for theta = 0 degrees are stable for all perturbation wavelengths and magnetic field strengths. This contradicts prior results in both slab and cylindrical geometry and suggests an error in this work.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA118074
Entities
People
- James D. Targove
Organizations
- Air Force Institute of Technology