Large eddy simulation of turbulent flow in Rayleigh-Benard configuration

Abstract

This work undertakes a numerical study of turbulent incompressible flows in Rayleigh-Benard configurations using Large Eddy Simulation and two sub-grid scale models, i.e., the WALE (Wall Adapting Local Eddy-viscosity) model and the corresponding dynamic sub-grid model (DSGS). In the process of using DSGS, an optimal value of constant  of the WALE model was determined for the envisaged Rayleigh number (Ra=6.3.10⁵). The computed numerical results (on a relatively coarse grid) showed good agreement with those Direct Numerical Simulation (DNS) results found in the literature. It is observed that the profiles obtained are highly dependent on the time interval over which the statistics are made (equivalent to the Interval of Statistical Analysis (ISA)).

Keywords -Turbulent natural convection, Finite volume method, Large eddy simulation.