In situ adjustment of a visco hyper elastic model for stretch blow molding process simulation of poly-ethylene terephthalate bottles

Simulation of the stretch blow molding (SBM) process necessitates to develop a model able to reproduce the material behavior at high strain rate, large deformation with temperature gradient. On the other hand, both the need to understand polyethylene terephthalate (PET) material characteristics and the final bottle performance requirements continue to get higher. That necessitates a regular update of the identification of the model. Bottle producers are interested by managing this identification without a specific complex apparatus not available in an industrial context. The work presented here describes an in-situ adjustment process for upgrading all parameters of a visco-hyperelastic (VHE) model from a small number of blowing tests that do not necessitate complex equipment. The accuracy of the adjustment process is validated through the ability of the updated VHE model to reproduce the final shape, the pressure evolution and the tension of the rod during an industrial blowing of PET bottles.