Stabilization of short-wavelength disturbances in the Rayleigh--Taylor instability of plastic solids by a surface layer of high yield strength
Abstract
The mechanical effects of a thin surface layer in reducing the growth of the Rayleigh-Taylor instability of a plastic solid plate is investigated by representing the surface layer as an elastic plate of high yield strength and high bonding strength to the plastic. This plate may be either the surface layer itself or a composite material formed by interactions of the surface layer with the solid surface layers. In this approximation it is found under wide ranges of conditions that short-wavelength disturbances are stabilized in linear approximation. In this limit the ''gravitational'' energy increment of the displaced plastic solid is overcome by the elastic shear energy of the stretched plate. Long-wavelength disturbances are very weakly affected by this mechanism. For a plastic plate of approximately 1-cm thickness subjected to a pressure difference of approximately 100 kbar we expect wavelengths shorter than lambda/sub c/ approximately 10/sup -1/ cm to be effectively stabilized by this mechanism.
- Authors:
- Publication Date:
- Research Org.:
- Los Alamos Scientific Lab., NM (USA)
- OSTI Identifier:
- 7258754
- Report Number(s):
- LA-6744-MS
TRN: 77-011613
- DOE Contract Number:
- W-7405-ENG-36
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; PLATES; RAYLEIGH-TAYLOR INSTABILITY; SOLIDS; PLASTICITY; VERY HIGH PRESSURE; INSTABILITY; MECHANICAL PROPERTIES; 656000* - Condensed Matter Physics
Citation Formats
Mjolsness, R.C. Stabilization of short-wavelength disturbances in the Rayleigh--Taylor instability of plastic solids by a surface layer of high yield strength. United States: N. p., 1977.
Web. doi:10.2172/7258754.
Mjolsness, R.C. Stabilization of short-wavelength disturbances in the Rayleigh--Taylor instability of plastic solids by a surface layer of high yield strength. United States. doi:10.2172/7258754.
Mjolsness, R.C. Tue .
"Stabilization of short-wavelength disturbances in the Rayleigh--Taylor instability of plastic solids by a surface layer of high yield strength". United States.
doi:10.2172/7258754. https://www.osti.gov/servlets/purl/7258754.
@article{osti_7258754,
title = {Stabilization of short-wavelength disturbances in the Rayleigh--Taylor instability of plastic solids by a surface layer of high yield strength},
author = {Mjolsness, R.C.},
abstractNote = {The mechanical effects of a thin surface layer in reducing the growth of the Rayleigh-Taylor instability of a plastic solid plate is investigated by representing the surface layer as an elastic plate of high yield strength and high bonding strength to the plastic. This plate may be either the surface layer itself or a composite material formed by interactions of the surface layer with the solid surface layers. In this approximation it is found under wide ranges of conditions that short-wavelength disturbances are stabilized in linear approximation. In this limit the ''gravitational'' energy increment of the displaced plastic solid is overcome by the elastic shear energy of the stretched plate. Long-wavelength disturbances are very weakly affected by this mechanism. For a plastic plate of approximately 1-cm thickness subjected to a pressure difference of approximately 100 kbar we expect wavelengths shorter than lambda/sub c/ approximately 10/sup -1/ cm to be effectively stabilized by this mechanism.},
doi = {10.2172/7258754},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 1977},
month = {Tue Mar 01 00:00:00 EST 1977}
}
-
The Rayleigh-Taylor instability response of elastic-plastic solids can be modeled by approximate means. However, neither the linear elastic response equation nor the so-called /open quotes/minimum amplitude/close quotes/ instability criterion derived from rigid plastic analyses is sufficient to describe overall stability characteristics at very large driving pressures. We compare several versions of the modal or one-degree-of-freedom approximation technique and indicate the common features which must be included to obtain the qualitative response seen in numerical experiments.
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Preliminary report of numerical simulations of intermediate wavelength collisional Rayleigh-Taylor instability in equatorial spread F. Memorandum report
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