Mold filling simulation in RTM processing of natural fiber composite materials. Experimental validation

CANDELA RODRIGUEZ LALLI; GASTON FRANCUCCI; JUAN MORAN

Kyoto

Conferencia; FPCM13 - The 13th International Conference on Flow Processes in Composite Materials; 2016

In contrast to synthetic fibers, the permeability of natural fiber reinforcements does not necessarily remain constant along the wetted region of the fabrics throughout the infiltration process, because the porosity can change as the fibers absorb fluid and swell. In a previous work, two models were presented to simulate the infiltration stage during RTM processing of natural fiber composites. The homogeneously variable permeability model (HVPM), considers that the permeability of the preform decreases with time due to fiber swelling, but the change in permeability is uniform throughout the entire wetted perform and is only a function of the injection time. The permeability field model (PFM), considers the fact that different regions of the wetted perform experience higher or lower fiber swelling depending on the amount of time that they have been immersed in the fluid. This leads to a field of permeability along the wetted fiber bed. Another interesting result was that since a permeability field along the wetted preform is generated because of the different immersion times experienced by each element, the global pressure distribution does not follow a linear behavior, as one would get from the models that consider a constant permeability value. In the present work, the validation of the PFM is presented by comparing the results predicted by the PFM with those observed experimentally.