2018/04/13 by Caterina Bassi, Antonella Abbà, Bassi, Caterina +5
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Advanced Numerical Methods in Computational Mathematics #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Fluid Dynamics and Vibration Analysis #Geological formations and processes #Ionosphere and magnetosphere dynamics
paper · pdf · doi:10.48550/arxiv.1804.04958
openalex publication_date 2018/04/13 · openalex created_date 2022/09/02 · openalex updated_date 2026/07/28
We present results of three-dimensional Direct Numerical Simulations (DNS)\nand Large Eddy Simulations (LES) of turbulent gravity currents with a\nDiscontinuous Galerkin (DG) Finite Elements method. In particular, we consider\nthe three-dimensional lock-exchange test case as a typical benchmark for\ngravity currents. Since, to the best of our knowledge, non-Boussinesq\nthree-dimensional reference DNS are not available in the literature for this\ntest case, we first perform a DNS experiment. The three-dimensional DNS allows\nto correctly capture the loss of coherence of the three-dimensional turbulent\nstructures, providing an accurate description of the turbulent phenomena taking\nplace in gravity currents. The DNS is then employed to assess the performance\nof different LES models. In particular, we have considered the Smagorinsky\nmodel, the isotropic dynamic model and an anisotropic dynamic model. The LES\nresults highlight the excessively dissipative nature of the Smagorinsky model\nwith respect to the dynamic models and the fact that the anisotropic dynamic\nmodel performs slightly better with respect to its isotropic counterpart.\n