Hydromechanical loading and compressibility of fibrous reinforcements

The manufacturing of large composite parts in the field of aeronautics is increasingly important. LCM processes (Liquid Composite Molding) are currently used. Infusion processes such as the Resin Film Infusion (RFI) are more and more used for the manufacturing of large parts. During this process, the resin flows through the fibrous medium under the stress created by a flexible membrane in the transverse direction of the reinforcement's plane. The compaction of the preforms and the flow of resin through the fibrous network take place simultaneously. There is, therefore, a coupled loading of the porous reinforcements. In order to better control this process, it is necessary to optimize resin pressure and fabric compression by using the appropriate simulating tools. It is also necessary to clarify which laws are suitable to model the process. To this objective, a new experimental device was set up to impose hydromechanical loadings to fibrous preforms. Results analyzing the hydromechanical couplings in saturated medium with flow rate conditions and a compression control with r stress conditions are presented and discussed in this work. A model simulating infusion processes [1] has also been used to analyse the compressibility behaviour of the fibrous reinforcement by using an inverse method.