TRANSPORT-EQUATIONS OF CONDITIONALLY AVERAGED REYNOLDS STRESSES FOR COMPUTATION OF TURBULENT FLOWS WITH INTERMITTENCY

The transport equations for conditionally averaged Reynolds stresses h ave been derived for use in computation of turbulent flows with interm ittency. In addition to terms corresponding to those appearing in conv entional transport equations, the conditional transport equations invo lve entrainment and interaction terms arising from the time-sharing of different zones of intermittent flows. The new terms have been examin ed using available experimental data taken in interacting shear flows. Careful treatment of these terms is generally required for proper mod elling. In certain cases, however, the magnitudes of the total of the extra terms are small and the evolution of the conditional Reynolds st resses are little influenced by the existence of the other zone.