Validation of Finite Element Model of a Tetra Pak Package

Abstract: There is a high dependency on accurate finite element models in the packaging industry for concept selection, design and virtual validation of packages. One of themost used materials for these packages is High-Density Polyethylene (HDPE). Thismaterial is highly anisotropic, strain rate dependent and has different behavior intension and compression.The objective of this thesis is to improve the existing constitutive model of HDPEthrough additional material characterization experiments and validate those models.For this purpose, strain rate dependencies of the material on elastic and hardeningresponse are included in the constitutive model. In addition to that, the compressivebehavior of HDPE was incorporated in the model as well. The anisotropy of HDPEwas modeled using the Hill48 yield criterion which was characterized by performingmultiple uniaxial tensile tests in the three directions: Machine Direction (MD), 45◦and Cross Direction (CD).Validation was done on the coupon test and compression test on the package.The result displayed that the results from the physical test are comparable with theresults obtained from the FE-models.From the tensile tests, the deformation of HDPE in MD and 45◦ was successfullycaptured and validated. While for the CD direction, the deformation could be captured but not validated against FE-model. Furthermore, the test results displayedthat the material HDPE exhibits a significant degree of anisotropy. In conclusion,the project contributed knowledge and understanding of how a Tetra Pak® packagebehaved during top load compression