Simulation of the gas-solid flow in the modified cyclones

Cyclones are widely used in the fields of air pollution control and gas-solid separation. But their separation efficiency has to be increased further especially for the large cyclones. Cone in the conical component bottom of the cyclone was one way to raise the total separation efficiency. But this improvement was not good for raising the grade separation efficiency of small particles. Three kinds of the revised cones with the vanes were used to improve the cyclone in the manuscript, which were the axial spiral vanes on the cone surface, straight vanes under the cone and on the vanes surface. The gas-solid flow, the static pressure and the separation efficiency were used to compare these cyclones. And the comprehensive properties of the straight vanes under the cone in these cyclones were the best from the simulation. Then the vanes number under the cone was further optimized. The cyclones with the vanes number 10, then 8 under the cone had the largest grade separation efficiency for particles great than or equal to 15μm, and had lower pressure drop and air leakage than the cyclone without the cone. And these two vanes numbers were recommended.