Intrinsic rotation produced by ion orbit loss and X-loss

Abstract

A practical calculation model for the intrinsic rotation imparted to the edge plasma by the directionally preferential loss of ions on orbits that cross the last closed flux surface is presented and applied to calculate intrinsic rotation in several DIII-D [J. Luxon, Nucl. Fusion 42, 614 (2002)] discharges. The intrinsic rotation produced by ion loss is found to be sensitive to the edge temperature and radial electric field profiles, which has implications for driving intrinsic rotation in future large tokamaks. V C 2012 American Institute of Physics. [http://dx.

The distribution of ion orbit loss fluxes of ions and energy from the plasma edge across the last closed flux surface into the scrape-off layer

“…1-9). Stacey et al [10][11][12][13][14] have recently extended the Miyamoto 6 model for numerical calculations of the effects of these "ion orbit losses" (IOLs) on the interpretation of edge plasma transport, and deGrassie et al, 15,16 Stacey et al, 17,18 and Pan et al 19,20 have shown that the peaking of toroidal rotation in the plasma edge observed in experiment could be interpreted as intrinsic rotation due to ion orbit loss.…”

Co-current rotation of the bulk ions due to the ion orbit loss at the edge of a tokamak plasma

“…Intrinsic rotation at the edge of a tokamak plasma due to the ion orbit loss has been studied theoretically by many authors [22,26,27,30]; these theoretical works based on the ion orbit loss model predict that the peak of the co-current rotation speed locates at the last closed flux surface (LCFS). However, the experimental observations [12,31] and the edge gyrokinetic simulations [21] indicate that the peak of the co-current rotation speed locates inside the LCFS.…”

“…This will result in the co-current plasma rotation. The parallel rotation of the bulk ions due to the ion orbit loss can be given by [27][28][29][30] 0,min…”

“…The ion orbit loss has long been thought to play an important role in generating the REF and the plasma rotation at the edge of a tokamak plasma [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30].…”

Extensions of ion orbit loss theory

“…11,12 Recently, the intrinsic rotation observed in DIII-D in the absence of an external torque has been explained by ion orbit loss of thermalized ions. [13][14][15][16][17] There is a school of thought which holds that the physics of the edge plasma is determined in large part by ion orbit loss-the free-streaming of ions from inner flux surfaces along drift orbits that cross the last closed flux surface and are lost to the plasma. There are two different basic mechanisms for ion orbit loss in the edge plasma.…”