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Title: The snowflake divertor

Abstract

The snowflake magnetic configuration is characterized by the presence of two closely spaced poloidal field nulls that create a characteristic hexagonal (reminiscent of a snowflake) separatrix structure. The magnetic field properties and the plasma behaviour in the snowflake are determined by the simultaneous action of both nulls, this generating a lot of interesting physics, as well as providing a chance for improving divertor performance. One of the most interesting effects of the snowflake geometry is the heat flux sharing between multiple divertor channels. The authors summarise experimental results obtained with the snowflake configuration on several tokamaks. Wherever possible, relation to the existing theoretical models is described. Divertor concepts utilizing the properties of a snowflake configuration are briefly discussed.

Authors:
 [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1241977
Alternate Identifier(s):
OSTI ID: 1226189
Report Number(s):
LLNL-JRNL-669814
Journal ID: ISSN 1070-664X; PHPAEN; TRN: US1600620
Grant/Contract Number:  
AC52-07NA27344
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 22; Journal Issue: 11; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION

Citation Formats

Ryutov, D. D., and Soukhanovskii, V. A. The snowflake divertor. United States: N. p., 2015. Web. doi:10.1063/1.4935115.
Ryutov, D. D., & Soukhanovskii, V. A. The snowflake divertor. United States. doi:https://doi.org/10.1063/1.4935115
Ryutov, D. D., and Soukhanovskii, V. A. Tue . "The snowflake divertor". United States. doi:https://doi.org/10.1063/1.4935115. https://www.osti.gov/servlets/purl/1241977.
@article{osti_1241977,
title = {The snowflake divertor},
author = {Ryutov, D. D. and Soukhanovskii, V. A.},
abstractNote = {The snowflake magnetic configuration is characterized by the presence of two closely spaced poloidal field nulls that create a characteristic hexagonal (reminiscent of a snowflake) separatrix structure. The magnetic field properties and the plasma behaviour in the snowflake are determined by the simultaneous action of both nulls, this generating a lot of interesting physics, as well as providing a chance for improving divertor performance. One of the most interesting effects of the snowflake geometry is the heat flux sharing between multiple divertor channels. The authors summarise experimental results obtained with the snowflake configuration on several tokamaks. Wherever possible, relation to the existing theoretical models is described. Divertor concepts utilizing the properties of a snowflake configuration are briefly discussed.},
doi = {10.1063/1.4935115},
journal = {Physics of Plasmas},
number = 11,
volume = 22,
place = {United States},
year = {2015},
month = {11}
}

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Cited by: 6 works
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Works referenced in this record:

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Regime of Improved Confinement and High Beta in Neutral-Beam-Heated Divertor Discharges of the ASDEX Tokamak
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A quarter-century of H-mode studies
journal, November 2007


Liquid-metal tokamak divertors
journal, December 1992


Distributed Divertor Radiation through Convection in DIII-D
journal, June 1997


Plasma convection induced by toroidal asymmetries of the divertor plates and gas puffing
journal, May 1997


Guidance of Divertor Channel by Cusp-Like Magnetic Field for Tokamak Devices
journal, March 2001

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Divertor geometry effects on detachment in TCV
journal, March 2001


Observations of High-Beta Toroidal Plasmas
journal, May 1981


On scrape off layer plasma transport
journal, May 2001


Effect of the magnetic field geometry on the flute-like perturbations near the divertor X point
journal, September 1993


Loss ion orbits at the tokamak edge
journal, October 1993


Chapter 8: Plasma operation and control
journal, June 2007


A fully implicit, time dependent 2-D fluid code for modeling tokamak edge plasmas
journal, December 1992


Edge-plasma models and characteristics for magnetic fusion energy devices
journal, July 2002


Large E×B convection near the divertor X-point
journal, March 2001


Electron Heat Transport in a Tokamak with Destroyed Magnetic Surfaces
journal, January 1978


“Snowflake” H Mode in a Tokamak Plasma
journal, October 2010


Concept Design of Optimized Snowflake Diverted Equilibria in CFETR
journal, April 2014


Calculation of Realistic Snowflake Equilibria for Next-Step Devices
journal, January 2013

  • Lackner, Karl; Zohm, Hartmut
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    Works referencing / citing this record:

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