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Experimental investigations of the effect of microchannel geometry on high-pressure dispersion and emulsification were carried out. Customized microchannels of varying geometric principles were fabricated in silicon and steel. In order to characterize the process efficiency of microchannel geometries, the effects of the process parameters (mean velocity, Reynolds number, and local pressure drop) were examined and correlated to the dispersion and emulsification results. It is demonstrated that high pressure losses focused at a small channel length and high velocity gradients lead to high stress intensities and, in consequence, to low particle or droplet sizes. Thus, 2D orifices were successfully further improved regarding their process efficiency by adding a third-dimension constriction.

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Micromechanical aggregate properties are correlated with stress conditions during the dispersion process in a stirred‐media mill. The fracture energy distribution of the aggregates measured via micro‐compression tests is compared with the stress energy distribution in a stirred‐media mill determined by CFD‐discrete element method simulations and by an analytical model. The simulations are likened with a previously conducted one‐way coupling. Furthermore, the rotor speed is varied to identify its influence on stress energy and number of contacts. Using the stress energy distribution and the measured fracture distribution, an effective dispersion fraction can be calculated and correlated with the dispersion progress.