Analysis of the quality of Large-Eddy Simulation in solving classical flows

• Grant number: 25/14008-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Engineering - Mechanical Engineering - Transport Phenomena
• Principal Investigator: Livia Souza Freire Grion
• Grantee: Charllys Emmanuel dos Santos Oliveira
• Host Institution: Instituto de Ciências Matemáticas e de Computação (ICMC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Given the high computational cost of Direct Numerical Simulation (DNS) for turbulent flows, the search for reduced-cost models such as Large Eddy Simulation (LES) is justified. The LES technique consists of resolving the larger-scale vortices and parameterizing the influence of the smaller scales through a subgrid-scale model. However, LES has sources of error, a major one being the modeling of the effects of the unresolved smaller scales. In this context, the main objective of the present work is to evaluate the quality of the LES technique for classical and well-documented phenomena in fluid mechanics. The methodology is based on the post-processing of simulation data previously generated from a code specialized in atmospheric simulations. The analysis will be performed using established quantitative criteria, such as the investigation of the resolved turbulent kinetic energy fraction, and also by comparing the results with direct numerical simulations and reference experimental data. With this, it is expected to judge the capability of the LES method to resolve classical flows, as well as the performance of different subgrid-scale models in various contexts. Thus, the work is justified by its contribution to the critical understanding of the quality of LES simulations, aiming to strengthen confidence in the results generated by the method and to favor its rigorous adoption.