Direct numerical simulation of a two-phase three-dimensional planar jet

摘要

To investigate dispersion and statistics of heavy particles in three-dimensional well-developed turbulent shear flows, direct numerical simulation is used to study a particle-laden, spatially-evolving planar jet with a moderate Reynolds number of 3000. The governing equations of the gas phase are solved by the fractional-step projection schemes with finite volume method. The particles are traced in the Lagrangian framework based on one-way coupling. The instantaneous distribution of heavy particles at intermediate Stokes numbers has non-uniform clustering spatial structure, which can be better characterized by the correlation dimension. However, from the statistical point of view, the particle dispersion and particle dynamics are found to be non-linearly monotonously dependent on the particle Stokes number when the flow is well-developed. The larger Stokes number leads to the higher ensemble-averaged slip velocity, the higher ensemble-averaged particle kinetic energy as well as the higher ensemble-averaged particle Reynolds number with approximate power scaling laws. In addition, it is demonstrated that the Stokes number has a profound effect on inter-particle relative velocity.