VGSTUDIO MAX: Simulating the mechanical properties of complex foam or granular microstructures using CT data
Whether foam structures in materials science or granular materials in soil science – estimating the mechanical properties of complex arbitrary microstructures is of high interest to numerous research fields. Frequently used structures are, e.g., metallic foams in lightweight sandwich structures. To predict the mechanical properties of the entire composite, precise models of the constituents are needed. A common approach to solve this problem is to use microstructural data such as relative density, pore size and average beam thickness for analytical models like those introduced by Gibson and Ashby [1]. These approaches allow to estimate mechanical properties of a given structure on a mean field. But realistic structures are usually not perfectly regular and can thus lead to significant deviations between model and reality. For this reason, numerical simulation is needed.
The software VGSTUDIO MAX from Volume Graphics provides analysis tools for both approaches. It enables either to derive statistical information about the microstructure or to determine the mechanical properties directly from volumetric images of the structure by applying mechanical models. The latter approach allows also to take irregularities like variations of the local material thickness and anisotropic behavior resulting from a geometrically oriented microstructure into account.
During the Workshop, the surface of a foam structure is determined using the locally adaptive subvoxel-accurate surface determination. Subsequently, microstructural statistics are derived by the Foam/Powder Analysis Module. The relative density is calculated as well as the cell diameter, beam thickness and principal orientation of the cells. This data is used for evaluating the analytical model by Gibson and Ashby.
Modeling of the full structure is carried out using the Structural Mechanics Simulation Module of VGSTUDIO MAX. It uses an immersed boundary method implementation for the microscale simulation of stress distributions directly on CT scans without the need of meshing. In order to utilize 3rd party simulation software, also the Volume Meshing Module can be applied to export the meshed microstructure to a large variety of FEA tools. This enables to create volume meshes of real structures with high precision at an incredible speed for your standard FEA-software.
[1] Gibson, L., & Ashby, M. (1997). Cellular Solids: Structure and Properties (Cambridge Solid State Science Series). Cambridge: Cambridge University Press. doi:10.1017/CBO9781139878326
Please visit the Volume Graphics webpage for more details.