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Title: A physics-informed deep learning model of the hot tail runaway electron seed

Journal Article · · Physics of Plasmas
DOI: https://doi.org/10.1063/5.0164712 · OSTI ID:2337795
ORCiD logo [1]
  1. Univ. of Florida, Gainesville, FL (United States); U.S. Department of Energy, Office of Fusion Energy Sciences

A challenging aspect of the description of a tokamak disruption is evaluating the hot tail runaway electron seed that emerges during the thermal quench. This problem is made challenging due to the requirement of describing a strongly non-thermal electron distribution, together with the need to incorporate a diverse range of multiphysics processes, including magnetohydrodynamic instabilities, impurity transport, and radiative losses. Here this work develops a physics-informed neural network (PINN) tailored to the solution of the hot tail seed during an axisymmetric thermal quench. Here, a PINN is developed to identify solutions to the adjoint relativistic Fokker–Planck equation in the presence of a rapid quench of the plasma's thermal energy. It is shown that the PINN is able to accurately predict the hot tail seed across a range of parameters, including the thermal quench timescale, initial plasma temperature, and local current density, in the absence of experimental or simulation data. The hot tail PINN is verified by comparison with direct Monte Carlo simulations, with excellent agreement found across a broad range of thermal quench conditions.

Research Organization:
Univ. of Florida, Gainesville, FL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
SC0024634
OSTI ID:
2337795
Journal Information:
Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 9 Vol. 30; ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

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