Plasma and Fusion Research

Volume 14, 3403150 (2019)

Regular Articles

Development of Extended Two-Point Model for Asymmetric Scrape-Off Layer
Apiwat WISITSORASAK1,2), Sébastien KAHN3), Bernard PÉGOURIÉ3), Jean-Francois ARTAUD3), Guido CIRAOLO3) and Cédric REUX3)
Department of Physics, King Mongkut's University of Technology Thonburi, Bangkok, Thailand
Theoretical and Computational Science Center, King Mongkut's University of Technology Thonburi, Bangkok, Thailand
CEA, IRFM, F-13108 Saint-Paul-les-Durance, France
(Received 8 January 2019 / Accepted 22 July 2019 / Published 25 September 2019)


The SYCOMORE code is a modular system code which aims at modelling future fusion power plants with all subsystems and to provide a global view of the whole plant. The code consists in different modules handling the different subsystems of the plant, from the core plasma to the conversion of heat to electricity. Among them, the divertor is one of the most important components and must withstand high heat load. While the complex magnetic configuration in tokamaks and the peculiar transport in the scrape-off layer (SOL) give rise to an asymmetry in the high field and low field energy fluxes, this issue should be properly addressed in SYCOMORE for quick and reliable predictions. In this work, the SOLDIV code which is a scrape-off-layer and divertor module in SYCOMORE has been used to investigate this asymmetry problem based on an extended two-point model. When the outgoing fluxes of particles and heat from the plasma core enter the SOL at the stagnation point, they split into two parts: one transporting to the inner divertor, and the other transporting to the outer divertor. By introducing the imbalance factor of the energy flux between the two divertor plates, the transport equations become a set of nonlinear equations that can be numerically solved for the densities and temperatures at both divertor plates and the stagnation point. Strong temperature and density differences at the targets can be found. The analysis results are validated with the transport code SolEdge2D-EIRENE for WEST test discharges. The simulation results for ITER are also investigated.


divertor, SOL-divertor, system code, two-point model, balloon transport

DOI: 10.1585/pfr.14.3403150


  • [1] P. Stangeby and G. McCracken, Nucl. Fusion 30, 1225 (1990).
  • [2] P.C. Stangeby et al., The plasma boundary of magnetic fusion devices, vol.224 (Institute of Physics Publishing Bristol, 2000).
  • [3] H. Bolt et al., J. Nucl. Mater. 307, 43 (2002).
  • [4] R. Pitts et al., J. Nucl. Mater. 438, S48 (2013).
  • [5] M. Roedig et al., Fusion Eng. Des. 61, 135 (2002).
  • [6] G. Federici et al., Fusion Eng. Des. 109, 1464 (2016).
  • [7] R. Wenninger et al., Nucl. Fusion 57, 016011 (2016).
  • [8] C. Reux et al., Nucl. Fusion 55, 073011 (2015).
  • [9] C. Reux et al., Fusion Eng. Des. (2018).
  • [10] A. Li-Puma, J.-C. Jaboulay and B. Martin, Fusion Eng. Des. 89, 1195 (2014).
  • [11] P. Ghendrih et al., J. Nucl. Mater. 438, S368 (2013).
  • [12] D. Galassi et al., Nucl. Fusion 57, 036029 (2017).
  • [13] A. Kallenbach et al., J. Nucl. Mater. 337, 381 (2005).
  • [14] J. Jean, Fusion Sci. Technol. 59, 308 (2011).
  • [15] W.H. Press, B.P. Flannery, S.A. Teukolsky, W.T. Vetterling et al., Numerical recipes, vol.2 (Cambridge university press Cambridge, 1989).
  • [16] D. Post, J. Abdallah, R. Clark and N. Putvinskaya, Phys. Plasmas 2, 2328 (1995).
  • [17] A. Mavrin, J. Fusion Energy 36, 161 (2017).
  • [18] D. Guilhem et al., J. Nucl. Mater. 196, 759 (1992).
  • [19] G. Telesca et al., Plasma Phys. Control. Fusion 53, 115002 (2011).
  • [20] L. Isoardi et al., J. Comput. Phys. 229, 2220 (2010).
  • [21] H. Bufferand et al., Nucl. Fusion 55, 053025 (2015).
  • [22] G. Ciraolo et al., Nucl. Mater. Energy 12, 187 (2017).
  • [23] C.S. Pitcher and P. Stangeby, Plasma Phys. Control. Fusion 39, 779 (1997).
  • [24] B. Braams, Contrib. Plasma Phys. 36, 276 (1996).
  • [25] D. Knoll, Nucl. Fusion 38, 133 (1998).