Hossen, M.K.; Mulayath Variyath, A.; Alam, J.M. Statistical Analysis of Dynamic Subgrid Modeling Approaches in Large Eddy Simulation. Aerospace2021, 8, 375.
Hossen, M.K.; Mulayath Variyath, A.; Alam, J.M. Statistical Analysis of Dynamic Subgrid Modeling Approaches in Large Eddy Simulation. Aerospace 2021, 8, 375.
Hossen, M.K.; Mulayath Variyath, A.; Alam, J.M. Statistical Analysis of Dynamic Subgrid Modeling Approaches in Large Eddy Simulation. Aerospace2021, 8, 375.
Hossen, M.K.; Mulayath Variyath, A.; Alam, J.M. Statistical Analysis of Dynamic Subgrid Modeling Approaches in Large Eddy Simulation. Aerospace 2021, 8, 375.
Abstract
In large eddy simulation (LES) of turbulent flows, the most critical dynamical processes to be considered by dynamic subgrid models to account for an average cascade of kinetic energy from the largest to the smallest scales of the flow is not fully clear. Furthermore, evidence of vortex stretching being the primary mechanism of the cascade is not out of the question. In this article, we study some essential statistical characteristics of vortex stretching and its role in dynamic approaches of modeling subgrid-scale turbulence. We have compared the interaction of subgrid stresses with the filtered quantities among four models using invariants of the velocity gradient tensor. This technique is a single unified approach to studying a wide range of length scales in the turbulent flow. In addition, it also provides a rational basis for the statistical characteristics a subgrid model must serve in physical space to ensure an appropriate cascade of kinetic energy. Results indicate that the stretching mechanism extracts energy from the large-scale straining motion and passes it onto small-scale stretched vortices.
Keywords
large eddy simulation; vortex stretching; subgrid model; isotropic turbulence
Subject
Physical Sciences, Fluids and Plasmas Physics
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
