Droplet Disruption in High-Pressure Valves

Droplets are disrupted, if they are deformed over a period of time tdef that is longer than a critical deformation time tdef.cr and if the deformation, described by the Weber number. We, exceeds a critical value [19]  

Herein, o is the external tension, responsible for droplet deformation, is the capillary pressure, y is the interfacial tension, x is the droplet diameter, and /d is its viscosity. 

In high-pressure systems, the disruption power is the homogenization pressure multiplied by the volume stream V. Therefore, the specific disruption energy is simply measurable by using the pressure difference Ap over the dismption system. 

When passing the emulsion several (n) times through the valve, orifice, or nozzle, this has to he multiphed by the number of passes n. With the specific disruption energy v. the Sauter mean droplet diameter can he calculated in case of well-defined flow conditions by the following process functions  

Isentropic turbulent flow [29] and microturbulences in cavitational flow [37-40]  

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