Plasma and Fusion Research

Volume 14, 3405078 (2019)

Regular Articles

Experimental Analysis on Variation of the Amount of Particles Passing Through Traveling Wave Direct Energy Converter
Kazuhiro SHIBATA, Hiromasa TAKENO, Kazuya ICHIMURA, Satoshi NAKAMOTO and Yousuke NAKASHIMA1)
Graduate School of Engineering, Kobe University, Kobe 657-8501, Japan
Plasma Research Center, University of Tsukuba, Tsukuba 305-8577, Japan
(Received 27 December 2018 / Accepted 22 March 2019 / Published 16 May 2019)


Traveling wave direct energy converter (TWDEC) was proposed as an efficient energy recovery device for 14.7 MeV protons produced by D-3He fusion reaction. Protons are velocity-modulated and bunched up, then induce traveling wave field which traps and decelerates themselves. In simulation experiments, it was found that the amount of particles was larger during application of modulation/deceleration field in the condition providing high efficiency than other conditions. This paper treats the phenomenon and will present results of analytical experiments and discussion. We found that ions were scattered due to modulation, and variation of the number of ions was corresponding to variation of deceleration effect. The possible mechanism of the phenomenon is scattering of particles due to bunching and its suppression due to trapping by deceleration field. In other words, high efficiency would be obtained by suppression of scattering.


TWDEC, constant deceleration scheme, dual-frequency modulation, scattering, particle trapping

DOI: 10.1585/pfr.14.3405078


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