Plasma and Fusion Research

Volume 15, 2403073 (2020)

Regular Articles

Development of a Molecular Dynamics Method with Heat Transfer into Bulk for Ion Injection into Materials
Seiki SAITO, Hiroaki NAKAMURA1,2), Keiji SAWADA3), Masahiro KOBAYASHI1,4), Kawamura GAKUSHI1,4) and Hasuo MASAHIRO5)
Yamagata University, Yonezawa 992-8510, Japan
1)
National Institute for Fusion Science, Toki 509-5292, Japan
2)
Nagoya University, Nagoya 464-8603, Japan
3)
Shinshu University, Nagano 380-8553, Japan
4)
The Graduate University for Advanced Studies, SOKENDAI, Toki 509-5292, Japan
5)
Kyoto University, Kyoto 615-8540, Japan
(Received 29 November 2019 / Accepted 13 July 2020 / Published 12 October 2020)

Abstract

When an ion or atom is injected into a target material, the incident energy increases the temperature around the injection point. Owing to the energy transfer to the surrounding atoms, the temperature of the material recovers to the initial temperature in the real system because heat is transferred to the bulk of material which consists of an almost infinite number of atoms. However, if we simulate the system by the molecular dynamics (MD) method, it is difficult to prepare a sufficiently large system to calculate the process of heat transfer to the bulk. Therefore, in this study, we develop an MD simulation model which includes the effect of heat transfer to the bulk by solving heat conduction equation. The simulation result shows that the process of heat removal proceeds on a time scale of approximately 1000 times slower than the time scale of the incident energy transfer from the incident atom to the target material.

Keywords

heat conduction, molecular dynamics, plasma material interaction, hydrogen, carbon, divertor, recycling

DOI: 10.1585/pfr.15.2403073

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