Numerical Simulation of Flow Pattern and Liquid-solid Flow in Sudden Pipe Expansion

In order to analyse the diffusion features of solid particles in sudden pipe expansion, the turbulence flow field inside sudden pipe expansion was simulated with some Reynolds Time-average Models and Large Eddy Simulation (LES). The results showed that simulation with LES could respond the vortex dissipation and the flow instability better than the others. And the solid particle diffusion in sudden pipe expansion was simulated with LES and Discrete Phase Models(DPM). The results showed that the diffusance of particles decreased as the number of St(p) increased, the bigger particles remained their original flow track more and influenced less by coherent vortex and turbulence discrete vortex of the flow field, and the flow field had stronger capability of carrying particles with small diameter of particles.