Account of longitudinal flow inhomogeneity in modeling of turbulent mixing layers and jets

Description of jet flows in the frame of Reynolds equations closed by SSG/LRR-$\omega$ differential Reynolds stress model is considered. The need for turbulent diffusion coefficients adjustment and taking into account the longitudinal inhomogeneity of jet flows is shown. Turbulent diffusion coefficients are calibrated using temporal mixing layer data. An extra source term accounting the longitudinal flow inhomogeneity is proposed which approaches the velocity profile of the mixing layer behind the step and the potential core length of free jets to the experimental data. The results of subsonic free plane jet computations in the frame of full Reynolds equations closed by the modified model are presented, and significant improvement in the description of this flow is demonstrated.