Micro injection molding is an efficient and low cost process for the large-scale replication of thermoplastic polymer microparts.Numerical simulation in cavity filling is important to mold design and process parameters setting before mold manufacture.A meshfree-based method for solving viscosity equations was proposed to simulate the filling process of micro injection molding.The N-S governing equations were discretized by using a particle approximate method of smooth particle hydrodynamics.Some physical properties

such as velocity

pressure

and temperature were investigated in the filling process.As an example

mold cavity filling simulation for a microneedle used in biomedical application was performed

and the results were consistent with experiment.Compared with the traditional mesh method

such as three dimensional finite element method

with corresponding node or particle number and process condition

the proposed meshfree method showed advantages of higher accuracy and calculation efficiency.