Control of long range turbulent transport with biasing in the tokamak scrape-off-layer
Cross-field transport in the SOL influences tokamak performance in particular regarding the divertor efficiency. Recent experiment evidence emphasizes non-exponential and/or flat SOL profiles that suggest a large perpendicular transport. A 2D fluid model based on the interchange instability to simulate the SOL turbulence was found to exhibits intermittent dynamics of the particle flux. We propose a control method that prevents long range transport events from reaching the far SOL: It consists in biasing the far SOL leading to a transport barrier which stops the propagation of these intermittent events. The best trade off is to localize the biased toroidal ring around the baffles. We show that such a control is achievable providing the strength of the barrier is strong enough. The investigation of the minimal biasing power required to achieve the control as well as its experimental estimate is performed.
Bibliographic Reference: An article published in: Journal of Nuclear Materials 337-339 (2005) 342-346
Availability: This article can be accessed online by subscribers, and can be ordered online by non-subscribers, at: http://probe.usp.br/cgi-bin/sciserv.pl?collection=journals&journal=00223115
Record Number: 200518082 / Last updated on: 2005-04-19
Original language: en
Available languages: en