Simulation and Reynolds stress modeling of particle-laden turbulent shear flows

Direct numerical simulation (DNS) is conducted of a homogeneous turbulent s hear flow laden with mono-size particles. The dispersed phase is simulated in the Lagrangian frame and the carrier phase is considered in the Eulerian manner. The coupling between the two phases is 'two-way' which allows inve stigation of the effects of the mass loading ratio and the particle time co nstant on both phases. A new Reynolds stress model (RSM) is developed based on a 'two-fluid' methodology in which both the carrier phase and the dispe rsed phase are considered in the Eulerian frame. Closures are suggested for the unclosed terms (including the pressure-velocity gradient) which manife st the effects of two-way coupling. The results generated by DNS are used t o determine the magnitudes of some of the empirical constants appearing in RSM. The final model predictions for all the components of the fluid, the p article, and fluid-particle Reynolds stresses are assessed via detailed com parisons against DNS data. (C) 1999 Elsevier Science Inc. All rights reserv ed.