Viscosity and mutual diffusion of deuterium-tritium mixtures in the warm-dense-matter regime

Journal Article · Wed Sep 15 00:00:00 EDT 2010 · Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print)

DOI:https://doi.org/10.1103/PHYSREVE.82.036404· OSTI ID:21464502

Kress, J D; Cohen, James S; Horner, D A; Collins, L A ^[1]; Lambert, F ^[2]

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1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2. CEA, DAM, DIF, F-91297 Arpajon (France)

We have calculated viscosity and mutual diffusion of deuterium-tritium (DT) in the warm, dense matter regime for densities from 5 to 20 g/cm{sup 3} and temperatures from 2 to 10 eV, using both finite-temperature Kohn-Sham density-functional theory molecular dynamics (QMD) and orbital-free molecular dynamics (OFMD). The OFMD simulations are in generally good agreement with the benchmark QMD results, and we conclude that the simpler OFMD method can be used with confidence in this regime. For low temperatures (3 eV and below), one-component plasma (OCP) model simulations for diffusion agree with the QMD and OFMD calculations, but deviate by 30% at 10 eV. In comparison with the QMD and OFMD results, the OCP viscosities are not as good as for diffusion, especially for 5 g/cm{sup 3} where the temperature dependence is significantly different. The QMD and OFMD reduced diffusion and viscosity coefficients are found to depend largely, though not completely, only on the Coulomb coupling parameter {Gamma}, with a minimum in the reduced viscosity at {Gamma}{approx_equal}25, approximately the same position found in the OCP simulations. The QMD and OFMD equations of state (pressure) are also compared with the hydrogen two-component plasma model.

• OSTI ID: 21464502
• Journal Information: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print), Vol. 82, Issue 3; Other Information: DOI: 10.1103/PhysRevE.82.036404; (c) 2010 The American Physical Society; ISSN 1539-3755
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BENCHMARKS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
COUPLING
DENSITY FUNCTIONAL METHOD
DEUTERIUM
DIFFUSION
EQUATIONS OF STATE
EV RANGE
HYDROGEN
MIXTURES
MOLECULAR DYNAMICS METHOD
PLASMA
PLASMA SIMULATION
TEMPERATURE DEPENDENCE
TRITIUM
VISCOSITY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CALCULATION METHODS
DISPERSIONS
ELEMENTS
ENERGY RANGE
EQUATIONS
EVALUATION
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
RADIOISOTOPES
SIMULATION
STABLE ISOTOPES
VARIATIONAL METHODS
YEARS LIVING RADIOISOTOPES