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arXiv · 2303.08662

TURB-Lagr. A database of 3d Lagrangian trajectories in homogeneous and isotropic turbulence

Luca Biferale·Fabio Bonaccorso·Michele Buzzicotti·Chiara Calascibetta
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Abstract

We present TURB-Lagr, a new open database of 3d turbulent Lagrangian trajectories, obtained by Direct Numerical Simulations (DNS) of the original Navier-Stokes equations in the presence of a homogeneous and isotropic forcing. The aim is to provide the community interested in data-assimilation and/or Lagrangian-properties of turbulence a new testing-ground made of roughly 300K different Lagrangian trajectories. TURB-Lagr data are influenced by the strong non-Gaussian fluctuations characteristic of turbulence and by the rough and non differentiable fields. In addition, coming from fully resolved numerical simulations of the original partial differential equations, they offer the possibility to apply a wide range of approaches, from equation-free to physics-based models. TURB-Lagr data are reachable at http://smart-turb.roma2.infn.it

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Luca Biferale, Fabio Bonaccorso, Michele Buzzicotti, Chiara Calascibetta. 2023-03-15. TURB-Lagr. A database of 3d Lagrangian trajectories in homogeneous and isotropic turbulence. https://arxiv.org/abs/2303.08662

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