Abstract

Experimental density and potential fluctuation data from a 2D probe array have been analysed to study the turbulent cascade in a toroidally confined magnetized plasma. The bispectral analysis technique used is from Ritz et al (1989 Phys. Fluids B 1 153) and Kim et al (1996 Phys. Plasmas 3 3998). It has been tested on Hasegawa–Wakatani turbulence simulation data and then applied to experimental data from the TJ-K torsatron. The analysis has been done in 2D wavenumber space. Analysis of simulated and experimental data recover the analytically known growth rate and dispersion relation for drift-wave turbulence. The density fluctuations, which at the realistic collisionality are advected as a passive scalar with the vorticity, show power transfer from large to small scales, while the spectral power in potential fluctuations, which represents the energy, is transferred as an inverse cascade to larger scales. This is the first experimental evidence for the dual turbulent cascade in a magnetized plasma.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.