Abstract: In the numerical simulation on gas-solid two-phase flow dynamic characteristics of a cyclone separator taking CFD-DPM（Computational Fluid Dynamics-Discrete Particle Model），the effects of operation conditions and geometrical parameters on the separator's performance were mainly investigated.The CFD-DPM was validated against experimental data with respect to the separation efficiency under the air inlet velocity of 8 and 16 m/s，and acceptable consistency were achieved between the simulated results and the experimental data.It indicates that CFD-DPM could accurately predict the performance of cyclone separators.With the increase of air inlet velocity，the separation efficiency and pressure drop show approximately exponential growth and parabolic growth.In the research on cyclone separator's performance，there were five significant geometrical factors which were inlet width，inlet height，diameter and penetration depth of the exhaust pipe，and length of the separator.With the increase of the height and width of inlet，as well as the diameter and penetration depth of exhaust pipe，the pressure drop and separation efficiency decreased.Though increasing the cyclone separator’s height would reduce the pressure drop，it had little effect on the separation efficiency.The influence of the vortex finder’s height and dust discharge diameter on the pressure drop and separation efficiency was negligible.

Key words: cyclone separator, geometrical parameters, separation efficiency, pressure drop, computational fluid dynamics, discrete particle model