(111c) Why Does the World Need a True Triaxial Tester?

In the paper the question will be addressed why it is important to perform more experimental research on powder flow behavior. It will be shown that the well-known flow function is not independent of the intermediate principal stress as is usually assumed. Also anisotropy has a large influence on the flow function and the measured anisotropic flow function is lower than the regular flow function. The reason for these findings is that the particles in the powder form structures that determine the macroscopic behaviour of the powder. This structure is a missing parameter in the powder flow theory. Only a True Triaxial Tester will be able to perform the precise experiments that are needed to validate the growing work that is done on Discrete Element Modeling with respect to powder flow.