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arXiv · 2502.11567

Minimum-dissipation model and symmetry-preserving discretization for scalar transport in a turbulent flow

Jing Sun·F. Xavier Trias·Roel Verstappen
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Abstract

This work extends the minimum-dissipation model of large-eddy simulation and symmetry-preserving discretization to account for active or passive scalar transport and complex physical mechanisms.This novel scalar-minimum-dissipation model exhibits several desirable properties. It includes the effect of scalar transport, in addition to shear, on the suppression and production of turbulence. It switches off at no-slip walls, ensuring accurate capture of near-wall flow behavior without needing a wall model. It also switches off in laminar and transitional flows so that it is capable of predicting laminar-turbulent transition. The new scalar-minimum-dissipation model combined with the symmetry-preserving discretization is successfully tested in a differentially heated cavity in OpenFOAM. The results show that the symmetry-preserving discretization significantly improves predictions of flow quantity and heat transfer on highly stretched meshes.

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Jing Sun, F. Xavier Trias, Roel Verstappen. 2025-02-17. Minimum-dissipation model and symmetry-preserving discretization for scalar transport in a turbulent flow. https://arxiv.org/abs/2502.11567

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