A computational model for determini ng the configuration and thickness o f cladding layer was presented.Liquid,mushy and
solid regions in laser cladding process we re considered as a continuum,and the continuum model for binary solid -liquid phase change system was used to simulate the velocity and tem perature fields,and a fixed -grid an d moving coordinate system were adop ted to deal with fluid flow and heat transfer problem involving mov ing heat source.The sensible enthalpy was used as a dependent variable in energy equation,and the terms including latent heat were merged in to source term.Based on Lambert -Beer equation and Mies theory,the inte raction between powder stream and laser beam was treated to fulfil t he situation of high powder concentr ation.The commercial software PHOENICS,to which several modules related with source terms,boundary conditions,interaction between powder stream and laser beam and config uration of cladding layer were appended,was used to accomplish the simulation.The results obtained by the simulation are coincident with those measured in experiment basically.