Element Test Experiments and Simulations: from Dry towards Cohesive Powders
نویسندگان
چکیده
Findings from experiments and particle simulations for dry and cohesive granular materials are presented with the goal to reach quantitative agreement between simulations and experiments. Results for the compressibility, tested with the FT4 Powder Rheometer are presented. The first simulation results involve the strain controlled uniaxial compression of frictionless polydisperse spheres in a biaxial box using a linear visco-elastic contact model. As main result, the evolution of pressure as a function of volume fraction is reported. Our anisotropic, uniaxial findings compare astonishingly well with results for purely isotropic compression. Concerning the second stress response, namely anisotropy, we present the evolution of the deviatoric stress as a function of the volume fraction, which cannot be measured with the FT4 experiment, but requires a bi-axial experiment.
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