Simulation of tokamak SOL and divertor region including heat flux mitigation by gas puffing

Journal Article · Sun Jan 01 04:00:00 EST 2012 · Journal of the Korean Physical Society

DOI:https://doi.org/10.3938/jkps.61.387· OSTI ID:1055199

Park, Jin Woo ^[1]; Na, Y S ^[1]; Hong, S H ^[2]; Ahn, J W ^[3]; Kim, D K ^[4]; Han, Hyunsun ^[5]; Shim, Seong Bo ^[6]; Lee, Hae June ^[6]

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1. Seoul National University, Seoul, S. Korea
2. National Fusion Research Institute, Daejon, South Korea
3. Oak Ridge National Laboratory (ORNL)
4. Agency Def Dev, Taejon, South Korea
5. National Fusion Research Institute, Taejon, South Korea
6. Pusan National University, Busan, Korea

Two-dimensional (2D), scrape-off layer (SOL)-divertor transport simulations are performed using the integrated plasma-neutral-impurity code KTRAN developed at Seoul National University. Firstly, the code is applied to reproduce a National Spherical Torus eXperiment (NSTX) discharge by using the prescribed transport coefficients and the boundary conditions obtained from the experiment. The plasma density, the heat flux on the divertor plate, and the D (alpha) emission rate profiles from the numerical simulation are found to follow experimental trends qualitatively. Secondly, predictive simulations are carried out for the baseline operation mode in Korea Superconducting Tokamak Advanced Research (KSTAR) to predict the heat flux on the divertor target plates. The stationary peak heat flux in the KSTAR baseline operation mode is expected to be 6.5 MW/m(2) in the case of an orthogonal divertor. To study the mitigation of the heat flux, we investigated the puffing effects of deuterium and argon gases. The puffing position is assumed to be in front of the strike point at the outer lower divertor plate. In the simulations, mitigation of the peak heat flux at the divertor target plates is found to occur when the gas puffing rate exceeds certain values, similar to 1.0 x 10(20) /s and similar to 5.0 x 10(18) /s for deuterium and argon, respectively. Multi-charged impurity transport is also investigated for both NSTX and KSTAR SOL and divertor regions.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1055199
• Journal Information: Journal of the Korean Physical Society, Journal Name: Journal of the Korean Physical Society Journal Issue: 3 Vol. 61; ISSN 0374-4884
• Country of Publication: United States
• Language: English