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arXiv · 2508.12762

TURB-Scalar. A large database of passive scalar fields advected by 2D Navier-Stokes in the turbulent inverse cascade regime

Chiara Calascibetta·Luca Biferale·Fabio Bonaccorso·Massimo Cencini
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Abstract

We introduce TURB-Scalar, an open-access database comprising approximately $400$ uncorrelated snapshots of two-dimensional turbulent velocity and passive scalar fields, obtained from the turbulent inverse cascade regime. These data are generated through Direct Numerical Simulations (DNS) of the advection-diffusion equation for a passive scalar, $\theta$, with resolution $N=4096$. The database serves as a versatile benchmark for the development and testing of both physics-based and data-driven modeling approaches. The scalar field exhibits intermittent statistics with universal anomalous scaling, making TURB-Scalar a valuable resource for studying turbulent transport phenomena. The database is available at http://smart-turb.roma2.infn.it.

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Chiara Calascibetta, Luca Biferale, Fabio Bonaccorso, Massimo Cencini. 2025-08-18. TURB-Scalar. A large database of passive scalar fields advected by 2D Navier-Stokes in the turbulent inverse cascade regime. https://arxiv.org/abs/2508.12762

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