Abstract: Preferential dispersion of the particles was numericallystudied in three types of turbulent flows, namely, the flow over abackward-facing step, the fully developed channel flow and the round jetflow. Gas-phase was simulated by means of large eddy simulation andparticle-phase was tracked by particle trajectory model. It's shown thatinertia particles have preferential dispersion in the three turbulent flows,and the property of preferential motion of the particles is related to theparticle following property. The particle preferential dispersions aredetermined both by particle inertia and by large eddy structures. Particleswith Stokes number in the order of magnitude 1 (based on the macrotime-scale of fluid flow) have the strongest preferential distribution inlarge scale structures and they tend to accumulate in the turbulent regionswith low vorticity or low fluctuating velocity.