Title: The effects of convergence ratio on the implosion behavior of DT layered inertial confinement fusion capsules

Abstract

The wetted foam capsule design for inertial confinement fusion capsules, which includes a foam layer wetted with deuterium-tritium liquid, enables layered capsule implosions with a wide range of hot-spot convergence ratios (CR) on the National Ignition Facility. In this paper, we present a full-scale wetted foam capsule design that demonstrates high gain in one-dimensional simulations. In these simulations, increasing the convergence ratio leads to an improved capsule yield due to higher hot-spot temperatures and increased fuel areal density. High-resolution two-dimensional simulations of this design are presented with detailed and well resolved models for the capsule fill tube, support tent, surface roughness, and predicted asymmetries in the x-ray drive. Our modeling of these asymmetries is validated by comparisons with available experimental data. In 2D simulations of the full-scale wetted foam capsule design, jetting caused by the fill tube is prevented by the expansion of the tungsten-doped shell layer due to preheat. While the impacts of surface roughness and predicted asymmetries in the x-ray drive are enhanced by convergence effects, likely underpredicted in 2D at high CR, simulations predict that the capsule is robust to these features. Nevertheless, the design is highly susceptible to the effects of the capsule support tent, whichmore » negates all of the one-dimensional benefits of increasing the convergence ratio. Indeed, when the support tent is included in simulations, the yield decreases as the convergence ratio is increased for CR > 20. Finally and nevertheless, the results suggest that the full-scale wetted foam design has the potential to outperform ice layer capsules given currently achievable levels of asymmetries when fielded at low convergence ratios (CR < 20).« less

Authors:

Haines, Brian M.  ^[1];

• Search DOE PAGES for author "Haines, Brian M."
• Search DOE PAGES for ORCID "0000-0002-3889-7074"

Yi, S. A. ^[1]; Olson, R. E. ^[1]; Khan, S. F. ^[2]; Kyrala, G. A. ^[1]; Zylstra, A. B.  ^[1];

• Search DOE PAGES for author "Zylstra, A. B."
• Search DOE PAGES for ORCID "0000-0003-0489-7479"

Bradley, P. A.  ^[1];

• Search DOE PAGES for author "Bradley, P. A."
• Search DOE PAGES for ORCID "0000-0001-6229-6677"

Peterson, R. R. ^[1]; Kline, J. L. ^[1]; Leeper, R. J.  ^[1];

• Search DOE PAGES for author "Leeper, R. J."
• Search DOE PAGES for ORCID "0000-0003-3986-620X"

Shah, R. C. ^[1]

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+ Show Author Affiliations

1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:

Mon Jul 10 00:00:00 EDT 2017

Research Org.:

Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1374335

Alternate Identifier(s):

OSTI ID: 1368606; OSTI ID: 1781752

Report Number(s):

LA-UR-17-23609; LLNL-JRNL-820815
Journal ID: ISSN 1070-664X

Grant/Contract Number:  

AC52-06NA25396; AC52-07NA27344

Resource Type:

Accepted Manuscript

Journal Name:

Physics of Plasmas

Additional Journal Information:

Journal Volume: 24; Journal Issue: 7; Journal ID: ISSN 1070-664X

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Plasma confinement; Computer simulation; Tectonophysics; Optical metrology; Metalloids