Research of structure formation and turbulence transport with two-dimensional plasma potential measurement

2015 Fiscal Year Final Research Report

• Project/Area Number: 25820441
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: National Institute for Fusion Science
• Principal Investigator: Shimizu Akihiro 核融合科学研究所, ヘリカル研究部, 助教 (00390633)
• Co-Investigator(Renkei-kenkyūsha): IDO TAKESHI 核融合科学研究所, ヘリカル研究部, 准教授 (50332185) ; FUJISAWA AKIHIDE 九州大学, 応用力学研究所, 教授 (60222262)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 電場構造 / 重イオンビームプローブ / 二次元計測 / ヘリカル / 乱流 / 帯状流

Outline of Final Research Achievements

For two-dimensional spatial potential profile measurements, automatic adjustment system is developed for the heavy ion beam probe (HIBP) on the Large Helical Device (LHD). The probe beam energy is changed shot by shot, and this automatic adjustment system is used to optimize beam trajectory on the beam transport line. Equilibrium 2D potential profile is successfully measured with the LHD-HIBP system. As for the fluctuation measurements, by analyzing correlation analysis between HIBP and magnetic probe signal, the noise level of the power spectrum of potential fluctuation is reduced. 2D structures of potential phase and amplitude of the 200 kHz MHD instability mode are successfully obtained. However, as for the turbulence measurements, signal to noise ratio is not enough and further improvement is expected.

Free Research Field

プラズマ計測