Parameter Identification of Fiber Orientation Models Based on Direct Fiber Simulation with Smoothed Particle Hydrodynamics

The behavior of fiber suspensions during flow is of fundamental importance to the process simulation of discontinuous fiber reinforced plastics. However, the direct simulation of flexible fibers and fluid poses a challenging two-way coupled fluid-structure interaction problem. Smoothed Particle Hydrodynamics (SPH) offers a natural way to treat such interactions. Hence, this work utilizes SPH and a bead chain model to compute a shear flow of fiber suspensions. The introduction of a novel viscous surface traction term is key to achieve full agreement with Jeffery’s equation. Careful modelling of contact interactions between fibers is introduced to model suspensions in the non-dilute regime. Finally, parameters of the Reduced-Strain Closure (RSC) orientation model are identified using ensemble averages of multiple SPH simulations implemented in PySPH and show good agreement with literature data

A holistic approach to use multi-scale fractions of dry carbon fibre production waste in filled Bulk Moulding Compounds (BMC)

The increasing demand for composites leads to a growing amount of end-of-life materialand production waste. The latter consists of a large fraction of unimpregnated fibre waste which is notsufficiently reprocessed using conventional textile processing procedures as they are either too expensiveor their mechanical performance is too low. Using pieces of dry non-crimp fabrics (patches) ina Bulk Moulding Compound process (BMC) displays a straightforward approach of fabric recycling.Adding fillers to the mixture not only offers the opportunity to modify mechanical and electrical propertiesas well as the costs but also a chance for a more holistic approach of dry fibre recycling, whenconventional fillers like chalk are replaced by ground recycled carbon fibres. In this way, all kindof dry fibre wastes can be reused in one process: Larger offcuts are chopped to smaller rectangularpatches whereas waste fractions of small offcuts are processed to carbon fibre powder as filler andprocessed together with resin to produce BMC materials. Mechanical investigations reveal that thepresented approach shows higher specific properties than the conventional filler without compromisingthe process and material quality.</jats:p