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arXiv · 1712.03170

Large eddy simulations using renormalized viscosity

Sumit Vashishtha·Anando Chatterjee·Abhishek Kumar·Mahendra K Verma
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Abstract

In this paper, we have used renormalized viscosity for performing large eddy simulations (LES) of decaying homogeneous and isotropic turbulence inside a periodic cube on coarse grids ($32^3$, $64^3$ and $128^3$) at initial Taylor Reynolds number ${\mathrm{Re}_{\lambda} \approx 315} $. The LES results were compared with direct numerical simulation (DNS) results on $512^3$ grid. We observe good agreement between LES and DNS results on the temporal evolution of turbulence kinetic energy ${E(t)}$, kinetic energy spectrum ${E_{u}(k)}$, kinetic energy flux ${\Pi_u(k)}$. The isosurfaces of velocity magnitude at a given time are similar for DNS and LES. This establishes the suitability of using renormalized viscosity for performing large eddy simulations.

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Sumit Vashishtha, Anando Chatterjee, Abhishek Kumar, Mahendra K Verma. 2017-12-08. Large eddy simulations using renormalized viscosity. https://arxiv.org/abs/1712.03170

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