1 School of Materials Science and Engineering, Shandong University of Technology, Zibo 255049, Shandong, China 2 Composite Center, AVIC Composite Corporation Ltd., Beijing 100095, China 3 Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, School of Materials Science & Engineering, University of Jinan, Jinan 250022, China 4 Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials(Ministry of Education), Shandong University, Jinan 250061, China
Aimed at ex-situ toughening technology and Z-direction RTM process, Darcy's law was modified by introducing the saturation parameter. The partial differential equation describing the unsteady flow of the resin in the fiber preform was established. The effect of process parameters such as volume flow rate, resin viscosity and fiber preform's permeability during the constant flow process on the injection pressure was investigated. The resin flow between intra-tow and inter-tow of the preform with untoughened layers and toughened layers was simulated. The results show that the numerical simulation results are reliable. The inner pressure in the fiber performs increases with the increase of injection time. The injection pressure increases linearly with the increase of volume flow rate and resin viscosity, while decreases with the increase of fiber preform's permeability, which accords with Darcy's law. The infiltration visualization of resin flow through meso-scale and micro-scale fiber preform is realized, which provides an important supplement for prediction of the macro-flow in fiber preforms and provides guidance for actual process.
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