Statistical Averaging in Variable Density Fluid Turbulent Motion

Abstract

This chapter is devoted to deriving statistical transport equations governing averaged single point properties of the flow field. It is only concerned with first (mean) and second order moments. Two different formulations will be mainly considered, referring to mean mass-conservative and non conservative evolutions. It is not intended for extensive and detailed presentations of the different formalisms — using either the classical formulation of the equations (“standard”, “mass-weighted” averaging,...) or the specific volume formulation —, but rather focuses on physical interpretation of density fluctuation correlations, according to mass conservative and non conservative mean flow analysis.