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NASA NTRS · 20240012512

Augmenting RANS Turbulence Models Guided by Field Inversion and Machine Learning

Abstract

This report investigates the use of a data-driven approach, viz., Field Inversion and Machine Learning (FIML), to improve conventional RANS turbulence models like the Spalart-Allmaras model and the Menter SST k-ω model. One of the crucial aspects of using an ML-based approach with limited training data to produce corrections that are generalizable to a large range of flow configurations is to design appropriate “features” (inputs to the ML model). A model, based on guidance from the FIML methodology, is presented in analytical form. An additional list of potential features is provided. Although these were not used in the present correction, they were considered in the course of its development, and are included to fully document the complete process employed in the present work.

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BibTeXRIS

Vishal Srivastava, Chris Rumsey, Gary Coleman, Li Wang. 2024-10-01. Augmenting RANS Turbulence Models Guided by Field Inversion and Machine Learning. https://ntrs.nasa.gov/citations/20240012512

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