Study on Voxel Finite Element Analysis of Open-Cell Polyurethane Foam

Establishment of a design method for the macroscopic stress-strain relationship of open-cell foam has been investigated because of the foam’s complicated microstructures. In this study, a material design method for the mechanical behavior of open-cell polyurethane foam using voxel finite element analysis is proposed to consider the microscopic structure and matrix properties. A finite-strain hyperelastic model was applied to a matrix of polyurethane foam. The Mooney-Rivlin model was adopted for the potential energy function of the hyperelastic model. To determine the mechanical properties of the matrix, original, solid specimens of polyurethane were prepared. The material parameters of the matrix were identified based on the tensile loading test results of the solid specimens. Microstructures of the open-cell polyurethane foam were determined using a CT-scanning system. Finite element models constrained by the original microstructural configurations were applied to numerical simulations. Periodic finite element models based on the modified microstructural configurations, the relative density of which was the same as that of the original models, were applied to the simulation. Based on the numerical results, verification of the design performance of the simulation code for open-cell polyurethane foam was performed. The simulation results were reasonably consistent with compression loading test results up to the plateau region.