Abstract Details
Abstracts
Author: Kyungjin Kim
Requested Type: Consider for Invited
Submitted: 2024-04-11 14:13:55
Co-authors: J.M. Park, M. Shafer, R.S. Wilcox, J.D. Lore, P. Snyder, G. Staebler, T.M. Wilks, T. Osborne
Contact Info:
Oak Ridge National Laboratory
1 Bethel Valley Rd
Oak Ridge, TN 37830
USA
Abstract Text:
A theory-based integrated modeling of Core, Edge pedestal, and Scrape-Off-Layer (CESOL) has been successfully tested against existing DIII-D super-H mode (SH) discharges for an optimized pedestal regime to simultaneously improve core performance and control plasma heat and particle exhaust. Recent DIII-D experiments utilized advanced controllers to expand the operating space of the super-H regime using a combination of plasma shape optimization, impurity seeding, deuterium gas puffing, and 3D magnetic perturbations. The core, edge pedestal and SOL regions are strongly coupled but governed by different physical processes, emphasizing the need for a quantitative understanding of the trade-offs of integration. This CESOL integration is built upon an Integrated Plasma Simulator (IPS) workflow empowered by high-performance computing, comprising three distinct but interconnected workflows: IPS-FASTRAN, IPS-EPED, and IPS-SOLPS-ITER. Several efficient coupling methods are also developed to improve consistency of the profiles across the pedestal and separatrix working toward SH discharges. A localized surrogate model for SOLPS-ITER is developed and employed to match total particle and energy fluxes at the separatrix, thereby determining the separatrix density and temperature for the boundary conditions of the EPED predictions. The response of the pedestal pressure with increasing separatrix density observed in experiments is reproduced by IPS-EPED. The core transport and confinement predicted by TGLF depend strongly on this pedestal condition determined by the CESOL simulations. Based on its reasonable interpretive capability in accordance with experimental findings against SH plasmas on DIII-D, CESOL will be employed for predictive modeling to optimize both the core and edge simultaneously for DIII-D shape and volume rise studies.
* Work supported in part by the US DOE under contracts DE-FC02-04ER54698, DE-SC0017992, DE-AC05-00OR22725, DE-SC0024399 and under FWP ERAT837
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