Modelling of the hiperdif method for manufacturing recycled composites using smoothed particle hydrodynamics

There has been a significant increase in the amount of carbon fibre reinforced polymer composite production in recent years with this trend set to continue in the future. With this increase in production comes an increase in waste. The High Performance Discontinuous Fibre (HiPerDiF) method invented at the University of Bristol is a technology enabling remanufacturing of carbon fibres reclaimed from end-of-life and production waste into recycled composite materials. It does this through a mechanism that ensures a high level of fibre alignment, a key requirement in order to produce commercially valuable, discontinuous fibre composites. The fibre alignment is enabled by spraying the short fibres, suspended in a water jet, between thinly spaced, parallel plates. This work models this fluid dynamics alignment mechanism using smoothed particle hydrodynamics. The results shown here validate the model against experiments by showing that the computational model captures the overall effect of changing the plate spacing on the fibre alignment. This is important to give confidence in using the model to investigate the physics behind the alignment in more detail.