Predictive modeling of NSTX discharges with the updated multi-mode anomalous transport module
Journal article, 2024

The objective of this study is twofold: firstly, to demonstrate the consistency between the anomalous transport results produced by updated Multi-Mode Model (MMM) version 9.0.4 and those obtained through gyrokinetic simulations; and secondly, to showcase MMM’s ability to predict electron and ion temperature profiles in low aspect ratio, high beta NSTX discharges. MMM encompasses a range of transport mechanisms driven by electron and ion temperature gradients, trapped electrons, kinetic ballooning, peeling, microtearing, and drift resistive inertial ballooning modes. These modes within MMM are being verified through corresponding gyrokinetic results. The modes that potentially contribute to ion thermal transport are stable in MMM, aligning with both experimental data and findings from linear CGYRO simulations. The isotope effects on these modes are also studied and higher mass is found to be stabilizing, consistent with the experimental trend. The electron thermal power across the flux surface is computed within MMM and compared to experimental measurements and nonlinear CGYRO simulation results. Specifically, the electron temperature gradient modes (ETGM) within MMM account for 2.0 MW of thermal power, consistent with experimental findings. It is noteworthy that the ETGM model requires approximately 5.0 ms of computation time on a standard desktop, while nonlinear CGYRO simulations necessitate 8.0 h on 8 K cores. MMM proves to be highly computationally efficient, a crucial attribute for various applications, including real-time control, tokamak scenario optimization, and uncertainty quantification of experimental data.

NSTX

predictive simulation

transport

multi-mode module

tokamak

Author

T Rafiq

Lehigh University

C. Wilson

Lehigh University

C. Clauser

Lehigh University

E. Schuster

Lehigh University

Jan Weiland

Lehigh University

Johan Anderson

Chalmers, Space, Earth and Environment

S. M. Kaye

Princeton University

A. Y. Pankin

Princeton University

B. P. LeBlanc

Princeton University

R. E. Bell

Princeton University

Nuclear Fusion

00295515 (ISSN) 17414326 (eISSN)

Vol. 64 7 076024

Subject Categories

Atom and Molecular Physics and Optics

Fusion, Plasma and Space Physics

DOI

10.1088/1741-4326/ad4d01

More information

Latest update

7/1/2024 1