The combination of particle foam with injection molding is a new process for cost-efficient mass production of future lightweight structures in the automotive sector. In the particle foaming process, particles of expanded polypropylene (EPP) are first injected into a mould and then get passed by steam. This melts the surface of the particles and joins them into a single component. However, the methods for the digital engineering this manufacturing processes and products made by it are not yet fully developed. In the joint project “Integral production of hybrid lightweight sandwich structures in particle foam composite injection moulding for mass production – SamPa”, funded by the BMBF, (funding code: 02P15Z004), inpro is currently working on the development of corresponding simulation methods. Both particle properties and flow processes are of decisive importance for the simulation of the filling process.

The inpro developers have now successfully simulated the filling process using a combination particle simulation (DEM) and flow simulation (CFD) considering the complete interactions. A complete set of physical properties of the particles is determined in experiments and considered in the simulation using models for elasticity, damping, friction and adhesion.