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Title: Hydrodynamic instabilities in ablative tamped flows

Abstract

Perturbation amplitudes and correlated growth rates of hydrodynamic instabilities in the compressed core of a directly driven inertial confinement fusion capsule are analyzed in planar and spherical geometries, with and without heat conduction. It is found that the maximum Lagrangian perturbation amplitude is always located inside the hot spot and not at the ablation front when heat conduction is switched on. A reduction of the Rayleigh-Taylor growth rate compared to the classical one is also shown. The growth rate is varying in k (against k{sup 1/2} classically), due to the unsteady state regime of the deceleration.

Authors:
; ; ;  [1];  [2]
  1. Av. de los Descubrimientos, 5, 1A, 13005, Ciudad Real (Spain)
  2. (France)
Publication Date:
OSTI Identifier:
20860446
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 12; Other Information: DOI: 10.1063/1.2397041; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABLATION; ACCELERATION; AMPLITUDES; CAPSULES; DISTURBANCES; GEOMETRY; HOT SPOTS; INERTIAL CONFINEMENT; LAGRANGIAN FUNCTION; MAGNETOHYDRODYNAMICS; PLASMA; RADIATION TRANSPORT; RAYLEIGH-TAYLOR INSTABILITY; REDUCTION; SPHERICAL CONFIGURATION; THERMAL CONDUCTION

Citation Formats

Temporal, M., Jaouen, S., Masse, L., Canaud, B., and CEA/DAM Ile-de-France, BP12, F-91680 Bruyeres-le-Chatel. Hydrodynamic instabilities in ablative tamped flows. United States: N. p., 2006. Web. doi:10.1063/1.2397041.
Temporal, M., Jaouen, S., Masse, L., Canaud, B., & CEA/DAM Ile-de-France, BP12, F-91680 Bruyeres-le-Chatel. Hydrodynamic instabilities in ablative tamped flows. United States. doi:10.1063/1.2397041.
Temporal, M., Jaouen, S., Masse, L., Canaud, B., and CEA/DAM Ile-de-France, BP12, F-91680 Bruyeres-le-Chatel. Fri . "Hydrodynamic instabilities in ablative tamped flows". United States. doi:10.1063/1.2397041.
@article{osti_20860446,
title = {Hydrodynamic instabilities in ablative tamped flows},
author = {Temporal, M. and Jaouen, S. and Masse, L. and Canaud, B. and CEA/DAM Ile-de-France, BP12, F-91680 Bruyeres-le-Chatel},
abstractNote = {Perturbation amplitudes and correlated growth rates of hydrodynamic instabilities in the compressed core of a directly driven inertial confinement fusion capsule are analyzed in planar and spherical geometries, with and without heat conduction. It is found that the maximum Lagrangian perturbation amplitude is always located inside the hot spot and not at the ablation front when heat conduction is switched on. A reduction of the Rayleigh-Taylor growth rate compared to the classical one is also shown. The growth rate is varying in k (against k{sup 1/2} classically), due to the unsteady state regime of the deceleration.},
doi = {10.1063/1.2397041},
journal = {Physics of Plasmas},
number = 12,
volume = 13,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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