Plasma and Fusion Research

Volume 15, 2404006 (2020)

Regular Articles

Void Free Fuel Solidification in a Foam Shell FIERX Target
Akifumi IWAMOTO, Takeshi FUJIMURA1) and Takayoshi NORIMATSU1)
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki 509-5292, Japan
Institute of Laser Engineering, Osaka University, Suita 565-0871, Japan
(Received 29 November 2019 / Accepted 3 February 2020 / Published 13 March 2020)


We study fuel layering for the Fast Ignition Realization EXperiment (FIREX) cryogenic target with a foam shell. A void free solid fuel layer within a porous foam material must be formed ideally. We have demonstrated the residual void fraction of ∼1% in a foam wedge with temperature controlled solidification. ANSYS simulations have shown that the residual void reduction technique will be applicable to the FIREX target. We examined each step in the simulated solidification process using a dummy foam shell target. In several attempts, solid fuel formation with a reduced void fraction in the foam shell succeeded.


fast ignition laser fusion, cryogenic target, foam shell, void free solid fuel layering

DOI: 10.1585/pfr.15.2404006


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