Stochastic coherent adaptive LES with time-dependent thresholding

Abstract

With the recent development of wavelet-based techniques for computational fluid dynamics, adaptive numerical simulations of turbulent flows have become feasible (Schneider and Vasilyev, 2010). Adaptive wavelet methods are based on wavelet threshold filtering that makes it possible to separate coherent energetic eddies, which are numerically simulated, from residual background flow structures that are filtered out. By varying the filter thresholding level different approaches with different fidelity are obtained: from the highly accurate wavelet-based direct numerical simulation (WDNS) that does not involve any model to the stochastic coherent adaptive large eddy simulation (SCALES) that needs a closure modeling procedure, i.e. (De Stefano et al., 2008).