Polymer is one of the most widely used materials due to its quality performance, and injection molding is one of the most widely employed methods of polymer processing. There is a complex, unsteady and non-isothermal process for polymer melts in injection molding, which has an important effect on the mechanical and optical performance of the molded part since the viscoelastic nature of the polymer results in development of shear and normal stresses and large elastic deformation during the filling stage and ...