000226474 001__ 226474
000226474 005__ 20180913064232.0
000226474 0247_ $$2doi$$a10.1088/0741-3335/58/12/124003
000226474 037__ $$aARTICLE
000226474 245__ $$aNeoclassical toroidal torque generation by auxiliary heating in non-axisymmetric tori
000226474 269__ $$a2016
000226474 260__ $$bIOP$$c2016
000226474 336__ $$aJournal Articles
000226474 520__ $$aIn conditions of ideal axisymmetry, for a magnetized plasma in a generic bounded domain, necessarily toroidal, the uniform absorption of external energy (e.g. rf or isotropic alpha heating) clearly cannot give rise to net forces or torques. A rather common experimental observation on contemporary tokamaks is that the near central absorption of auxiliary heating power (often ICH, ECH, and LHCD) and current drive in presence of non axisymmetric magnetic perturbations, including tearing modes, drives a bulk plasma rotation in the co − Ip direction. Also growing tearing modes provide a nonlinear magnetic braking that tends to flatten the rotation profile and clamp it at the q-rational surfaces. The physical origin of the
 torque associated with Paux absorption could be due the effects of asymmetry in deposition or in the equilibrium configuration, but here we consider also the effect of the response of the so called neoclassical offset velocity to the power dependent heat flow increment. The neoclassical toroidal viscosity (NTV), due to error fields, internal magnetic kink or tearing modes tends to relax the plasma rotation to this asymptotic speed, which in absence of auxiliary heating is of the order of the ion diamagnetic velocity. It can be shown by a kinetic calculation, this offset velocity is a function of the absorbed heat and therefore of the injected auxiliary power, thereby forcing the plasma rotation in a direction opposite to the initial, to large values. The problem is discussed in the frame of the theoretical models of neoclassical toroidal viscosity.
000226474 6531_ $$anuclear research
000226474 6531_ $$afusion
000226474 6531_ $$atokamak
000226474 6531_ $$arotation
000226474 6531_ $$amhd
000226474 6531_ $$aneoclassical
000226474 6531_ $$aNTV
000226474 700__ $$aLazzaro, E
000226474 700__ $$aNowak, S
000226474 700__ $$aSauter, O
000226474 773__ $$j58$$q124003$$tPlasma Physics and Controlled Fusion
000226474 8564_ $$uhttp://iopscience.iop.org/0741-3335$$zURL
000226474 8564_ $$uhttps://crpplocal.epfl.ch/pinboard/jpapers/1701401.pdf$$zURL
000226474 909C0 $$0252028$$pSPC
000226474 909CO $$ooai:infoscience.tind.io:226474$$pSB$$particle
000226474 937__ $$aEPFL-ARTICLE-226474
000226474 970__ $$a17014/CRPP
000226474 973__ $$aOTHER$$rREVIEWED$$sPUBLISHED
000226474 980__ $$aARTICLE