Abstract: In order to improve the properties of fluidized bed based powder feeder for laser cladding,3-D unsteady gas-solid two-phase flow during the powder feeding process was simulated with FLUENT software.The simulation results of Ni-based alloy powder feeding process in Syamlal-O'Brien,Gidaspow,Mckeen and modified Syamlal-O'Brien drag law model were compared,which show that the mass flow rate obtained from Mckeen drag model is consistent well with the experimental results.And the simulation results of different fluidizing gas flow rate also agree well with the experimental results,which indicate that Mckeen model is suitable to simulate this kind of powder feeder.Fluidizing characteristics of gas-solid flow rate in 2.6L/min were analyzed,which shows that fluidizing gas flow inlet 2 has little effect on powder feeding.Thus fine powder delivering characteristics can also be achieved without fluidizing gas flow inlet 2.Therefore,the numerical simulation in Mckeen model can provide a theoretical basis for optimization of powder feeder for laser cladding.