Numerical study of non-isothermal turbulent jets by two k-ε closure models

This article presents a numerical study of a non-isothermal axisymmetric turbulent jet by two k-epsilon closure models based on Favre or Reynolds averaging, respectively. The numerical results are in good agreement with the experimental ones found in the literature. We show, in particular the advantage of treating separately the turbulent mass flux terms and their contribution to predicting variable density effects. A mixing efficiency definition is finally introduced. It is observed that the mixing efficiency increases when the density ratio between the turbulent jet and the ambient gas is reduced. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.