Progressive augmentation of Reynolds stress tensor models for secondary flow prediction by computational fluid dynamics driven surrogate optimisation

TL;DR

This paper introduces a progressive surrogate optimisation method to enhance turbulence models for secondary flow prediction, improving accuracy while maintaining performance on canonical cases.

Contribution

It presents a novel multi-objective optimisation approach to augment Reynolds stress models, specifically improving secondary flow prediction without losing original model accuracy.

Findings

Enhanced secondary flow prediction in test cases

Models preserve performance on canonical flows

Significant improvement in unseen case accuracy

Abstract

Generalisability and the consistency of the a posteriori results are the most critical points of view regarding data-driven turbulence models. This study presents a progressive improvement of turbulence models using simulation-driven surrogate optimisation based on Kriging. We aim for the augmentation of secondary-flow reconstruction capability in a linear eddy-viscosity model without violating its original performance on canonical cases e.g. channel flow. Explicit algebraic Reynolds stress correction models (EARSCMs) for $k-\omega$ SST turbulence model are obtained to predict the secondary flow which the standard model fails to capture. The optimisation of the models is achieved by a multi-objective approach based on duct flow quantities, and numerical verification of the developed models is performed for various test cases. The results of testing new models on channel flow cases guarantee that new models preserve the performance of the original $k-\omega$ SST model. Regarding the generalisability of the new models, results of unseen test cases demonstrate a significant improvement in the prediction of secondary flows and streamwise velocity. These results highlight the potential of the progressive approach to enhance the performance of data-driven turbulence models for fluid flow simulation while preserving the robustness and stability of the solver.