Experimental Investigation of Particle Pinch Associated with Turbulence in LHD Heliotron and JT-60U Tokamak Plasmas
نویسندگان
چکیده
Comparative studies were carried out to elucidate the most essential parameter(s) for control of density profiles in LHD heliotron and JT-60U tokamak plasmas. Different collisionality dependence was found between two devices. Change of fluctuation property was observed at different density profile in both devices in plasma core region. In JT-60U, increase of radial correlation length was observed at higher power of neutral beam heating (PNB) with increase of density peaking. In magnetic axis positions (Rax) at 3.6m of LHD, the peak wavenumber did not change at higher PNB with decrease of density peaking. The simple mixing length estimation shows larger contribution of turbulence driven transport in JT-60U compared with Rax=3.6m of LHD.
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