Based on the gas-liquid-solid three-phase model

the concerned equations suitable for the 3D flow field were derived for calculating virtual velocity and motion of fiber

and momentum exchange source term.A 3D model of the filling process for short fiber reinforced polymer melts was developed accordingly.3D dynamic simulation was performed by using the finite volume method on non-staggered grids and the Level Set method of capturing melts interface.On this basis

a new model was presented to calculate the mechanical properties parameters of 3D oriented short fiber reinforced composites according to the simulated oriented angle of fibers.Numerical results showed that 3D technology could be used to simulate effectively the flow process with the fountain effect of melts and fibers in injection molding.The fiber orientation analysis showed quantifiably the skin-core-skin structure

namely

the fibers in the skin region had a tendency to align along the melts flow direction

while the ones in the core region were randomly oriented.The calculated elastic modulus were in good agreement with the experimental values

which further demonstrated that the proposed gas-liquid-solid three-phase model and the relative algorithms could be used as a base for predicting composite properties.