A CFD-based approach to study cavitation in high-pressure homogenizer valves. Part 2. Cavitation intensity

Hydrodynamic cavitation take place in high-pressure homogenizer (HPH) valves. Cavitation wear, free radical formation and ultrasonic emissions are linked to the cavitation intensity. Cavitation intensity is also a key factor to understand any effect cavitation might have on particle breakup. Based on an approach used in previous studies on other devices, this contribution applies and tests a modelling framework for predicting and understanding cavitation intensity in a HPH valve. Effects of homogenizing pressure and backpressure are studied. Results show an increase in cavitation intensity with homogenizing pressure. The cavitation implosion induced dissipation rate of energy in a HPH is substantially lower than the dissipation rate of turbulent kinetic energy, which helps to explain previously reported empirical findings showing that cavitation does not break emulsion drops in HPHs. This contribution shows the importance of distinguishing between extent and intensity when discussing cavitation in HPH valves.