Saved in:
Bibliographic Details
Main Authors: Wu, Chutian, Zhang, Xin-Lei, Xu, Duo, He, Guowei
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2505.05716
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910934745743360
author Wu, Chutian
Zhang, Xin-Lei
Xu, Duo
He, Guowei
author_facet Wu, Chutian
Zhang, Xin-Lei
Xu, Duo
He, Guowei
contents Learning symbolic turbulence models from indirect observation data is of significant interest as it not only improves the accuracy of posterior prediction but also provides explicit model formulations with good interpretability. However, it typically resorts to gradient-free evolutionary algorithms, which can be relatively inefficient compared to gradient-based approaches, particularly when the Reynolds-averaged Navier-Stokes (RANS) simulations are involved in the training process. In view of this difficulty, we propose a framework that uses neural networks and the associated feature importance analysis to improve the efficiency of symbolic turbulence modeling. In doing so, the gradient-based method can be used to efficiently learn neural network-based representations of Reynolds stress from indirect data, which is further transformed into simplified mathematical expressions with symbolic regression. Moreover, feature importance analysis is introduced to accelerate the convergence of symbolic regression by excluding insignificant input features. The proposed training strategy is tested in the flow in a square duct, where it correctly learns underlying analytic models from indirect velocity data. Further, the method is applied in the flow over the periodic hills, demonstrating that the feature importance analysis can significantly improve the training efficiency and learn symbolic turbulence models with satisfactory generalizability.
format Preprint
id arxiv_https___arxiv_org_abs_2505_05716
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A framework for learning symbolic turbulence models from indirect observation data via neural networks and feature importance analysis
Wu, Chutian
Zhang, Xin-Lei
Xu, Duo
He, Guowei
Fluid Dynamics
Learning symbolic turbulence models from indirect observation data is of significant interest as it not only improves the accuracy of posterior prediction but also provides explicit model formulations with good interpretability. However, it typically resorts to gradient-free evolutionary algorithms, which can be relatively inefficient compared to gradient-based approaches, particularly when the Reynolds-averaged Navier-Stokes (RANS) simulations are involved in the training process. In view of this difficulty, we propose a framework that uses neural networks and the associated feature importance analysis to improve the efficiency of symbolic turbulence modeling. In doing so, the gradient-based method can be used to efficiently learn neural network-based representations of Reynolds stress from indirect data, which is further transformed into simplified mathematical expressions with symbolic regression. Moreover, feature importance analysis is introduced to accelerate the convergence of symbolic regression by excluding insignificant input features. The proposed training strategy is tested in the flow in a square duct, where it correctly learns underlying analytic models from indirect velocity data. Further, the method is applied in the flow over the periodic hills, demonstrating that the feature importance analysis can significantly improve the training efficiency and learn symbolic turbulence models with satisfactory generalizability.
title A framework for learning symbolic turbulence models from indirect observation data via neural networks and feature importance analysis
topic Fluid Dynamics
url https://arxiv.org/abs/2505.05716