Numerical Investigation on the Influence of Turbulence Fluctuations Over Wind Engineering Problems Using Large Eddy Simulation and a Synthetic Inflow Turbulence Generator

Abstract

A numerical investigation to study the influence of inflow turbulence fluctuations over predictions obtained from wind engineering applications using Large Eddy Simulation (LES) is performed in this work. It is well known that accurate LES results can be obtained if the inflow boundary conditions imposed on the computational domain satisfy prescribed spatial correlations and other turbulence characteristics. In order to reproduce experimental predictions obtained from wind tunnel tests and full-scale measurements, a synthetic turbulence generator is adopted here to produce velocity fluctuations over a specified region of the inflow plane considering the von Karman spectrum and the divergence-free condition.
A numerical model based on the Finite Element Method (FEM) and the explicit two-step Taylor-Galerkin algorithm is employed in this work to simulate wind flows, where turbulence is also simulated by using LES with the classic and dynamic sub-grid scale models. Some numerical analyses are carried out with the present scheme and results are compared with experimental and numerical predictions obtained by other authors.