Three-dimensional flow visualization experiment of an RTM injection for a GFRP cuff mold

This work presents a three-dimensional flow visualization of the injection process for a glass fiber reinforced plastic (GFRP) beam-column connection also known as a GFRP cuff. Previous work on flow visualization is extended by highlighting the stage-wise process of the injection and the dependence on three-dimensional qualities. The work also provides finite element model adaptations suggested by three physical flow experiments performed in a GFRP cuff mold. The first experiment revealed the nature of the injection in the actual GFRP cuff mold; the second explored the effects of varying the size of void spaces and cutting channels in the fibers; the last experiment shows that small deflections of the mold allow the resin to flow freely to channels which distribute resin into the fibers. The final section of this paper provides the results of a finite element model of the injection process. The results reveal that including the adaptations suggested by the experiments greatly increases the accuracy of the numerical simulation.

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