CD Technical Meeting (ML13): Surrogate models for tokamak MHD: parameter and state inference using Ensemble Kalman Filtering
Machine Learning, Uncertainty Quantification and Data Science
This talk explores the application of ensemble Kalman filtering (EnKF) to the study of tokamak instabilities, with a focus on combining data-driven approaches with reduced-order, surrogate models. While surrogates capture qualitative features of tokamak instabilities, relating them directly to experimental observations requires parameter and state inference via noise-robust data assimilation framework.
The talk begins with a brief introduction to the theory of ensemble Kalman filters and their role in data assimilation. This is followed by a description of a Python-based implementation adapted during my PhD, demonstrating how EnKF can be coupled with surrogate models for parameter and state inference. A worked example is presented to illustrate the structure and functionality of the code, and how it can be readily applied to experimental data.
Finally, the strengths and limitations of this approach are discussed when using EnKF for parameter inference.