Horizontal Approximate Deconvolution for Stratified Flows: Analysis and Computations

Abstract

Summary. In this paper we propose a new Large Eddy Simulation model derived by approximate deconvolution obtained by means of wave-number asymptotic expansions. This LES model is designed for oceanic flows and in particular to simulate mixing of fluids with different temperatures, density or salinity. The model -which exploits some ideas well diffused in the community-is based on a suitable horizontal filtering of the equations. We prove some a-priori estimates, showing certain mathematical properties and we present also the results of some preliminary numerical experiments.

On the Boussinesq system: regularity criteria and singular limits

“…We started a numerical study of these equations to describe mixing, since it is one of the most important processes to understand and predict transport of pollutants as well as the details of thermohaline circulation, see [9,11,14]. In the numerical approach one is forced to use approximate models: Direct numerical simulations -despite the increase in the available computational power-are still not effective, since the scales in the ocean circulation cannot be all resolved simultaneously.…”

A Non-Fickian Mixing Model for Stratified Turbulent Flows

“…Of these, two (Özgökmen et al, 2011;) contain a detailed analysis of mixed layer instability (MLI) with particular emphasis on sampling strategies using LES. Two papers focus on subgrid-scale models, in LES (Berselli et al, 2011) and in ocean models (Marques and Özgökmen, 2012). Our approach in Özgökmen et al (2012) is perhaps the first truly multi-scale LES aiming to dissect the interaction between the submesoscale MLI and deep mesoscale baroclinic instability, and how their multi-scale signature can be detected on the basis of scale-dependent relative dispersion plots.…”