Abstract: Resin flow is the major mechanism affecting the fiber content , void content and laminate dimension during the hot pressing process. Based on the effective st ress principle and Darcy law , a mathematic model and the
corresponding finite element model were developed to simulate the resin flow and fiber compaction process. With the numerical simulation system , the fiber distribution can be predicted in the laminate. The effects of the temperature boundary and lay-up type of the fiber bed on the resin flow process were studied. It was found that the temperature boundary has a large influence on the numerical results while the lay-up type largely affect s the laminate thickness and fiber dist ribution. At the same time , it was validated that the accuracy of the boundary condition and material parameters impact s the reliability of the simulated results. For the T700S/ epoxy 5228 unidirectional laminates ,there was a good agreement between the numerical and experimental data.