On the specificity between mapping of initial and final states of the magneto Rayleigh-Taylor instability

Technical Report · Tue Sep 27 04:00:00 EDT 2022

DOI:https://doi.org/10.2172/1889515· OSTI ID:1889515

Lewis, William ^[1]; Ruiz, Daniel ^[2]; Broeren, Theodore ^[3]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
3. Univ. of Arizona, Tucson, AZ (United States)

In this LDRD we investigated the application of machine learning methods to understand dimensionality reduction and evolution of the Rayleigh-Taylor instability (RTI). As part of the project, we undertook a significant literature review to understand current analytical theory and machine learning based methods to treat evolution of this instability. We note that we chose to refocus on assessing the hydrodynamic RTI as opposed to the magneto-Rayleigh-Taylor instability originally proposed. This choice enabled utilizing a wealth of analytic test cases and working with relatively fast running open-source simulations of single-mode RTI. This greatly facilitated external collaboration with URA summer fellowship student, Theodore Broeren. In this project we studied the application of methods from dynamical systems learning and traditional regression methods to recover behavior of RTI ranging from the fully nonlinear to weakly nonlinear (wNL) regimes. Here we report on two of the tested methods SINDy and a more traditional regression-based approach inspired by analytic wNL theory with which we had the most success. We conclude with a discussion of potential future extensions to this work that may improve our understanding from both theoretical and phenomenological perspectives.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: NA0003525
• OSTI ID: 1889515
• Report Number(s): SAND2022-12895R; 710222
• Country of Publication: United States
• Language: English

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