Effect of Microchannel Geometry on High‐Pressure Dispersion and Emulsification

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.