A three-phase integrated flow-stress model for processing of composites

An extension of the previously developed two-phase integrated flow-stress process model for composites is presented here to account for the presence of the gas phase. The extended model incorporates the multi-physics phenomena involving flow of both the resin and gas phases through the fibre-bed as well as the previously considered thermochemical transformations during resin cure. The model is implemented in a 2D plane strain u-v-P finite element code developed in MATLAB. Numerical examples with varying initial contents of gas and resin are presented to demonstrate the capability of the three-phase integrated flow-stress model to predict the flow-compaction and stress development during the curing process of thermoset composite materials. The interactive effects of resin flow, gas flow and stress development are investigated in order to shed light on the efficacy of the model in capturing the overall response of the composite material during processing.