Turbulent mixing by the interfacial instabilities in magnetized plasmas

2017 Fiscal Year Final Research Report

• Project/Area Number: 26287147
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Plasma science
• Research Institution: Osaka University
• Principal Investigator: Sano Takayoshi 大阪大学, レーザー科学研究所, 助教 (80362606)
• Co-Investigator(Kenkyū-buntansha): 森田 太智 九州大学, 総合理工学研究院, 助教 (30726401) ; 西原 功修 大阪大学, レーザー科学研究所, 名誉教授 (40107131) ; 坂和 洋一 大阪大学, レーザー科学研究所, 准教授 (70242881)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: レーザー宇宙物理学 / 磁気流体不安定 / レーザー実験

Outline of Final Research Achievements

We have investigated interfacial instabilities, such as Richtmyer-Meshkov instability, in magnetized plasmas by numerical simulations and laboratory laser experiments. Theoretically, it is found that the magnetic field can reduce the growth of the Richtmyer-Meshkov instability significantly. When the seed field is relatively weak, it can be amplified by the fluid motions. The critical field strength is given by the Alfven number defined by the ratio of the growth velocity and Alfven speed at the interface. To confirm these effects, we performed laser plasma experiments by using the GEKKO laser system in Osaka University. The growth of the interface fluctuations has been observed successfully by optical radiography method. In addition, the B-dot probe have measured the signals of amplified magnetic field through the turbulent motions driven by the interfacial instabilities.

Free Research Field

天体プラズマ物理学