Publication on prediction of the in-plane permeability and air evacuation time of fiber-placed TPC preforms
A paper about the prediction of the in-plane permeability and air evacuation time of fiber-placed thermoplastic composite (TPC) preforms with engineered intertape channels was published by Lars Niens, Senior Research Engineer at the TPRC. The publication presents a simulation tool that can predict which intertape channel dimensions lead to effective in-plane air evacuation.
During vacuum-bag-only (VBO) consolidation of TPCs there are two main void removal mechanisms: through-thickness diffusion and in-plane air evacuation. The automated fiber placement (AFP) process allows for the creation of preforms with an engineered intertape channel network by introducing spacing between the tapes. This space can facilitate air evacuation during VBO consolidation. In Lars' research paper a predictive simulation method is developed to optimize the intertape channel dimensions for effective in-plane air evacuation.
The results from the models indicated that in-plane air evacuation through the engineered intertape channel network is quick, and it takes only a few minutes to evacuate 99% of the air from large preforms like fuselage panels.
