In this work, we report on the behavior of hydroentangling waterjets issued from a conecapillary nozzle at different configurations of cone-up and cone-down under pressures up to 250 bars. The differences between these two configurations are analyzed via unsteadystate fluid dynamics simulations, which indicated existence of permanent cavitation in the cone-up and a so-called hydraulic flip in the cone-down nozzle. In particular, we have shown that hydraulic flip causes the ambient air to move upward into the nozzle and separate the water flow from the nozzle wall protecting the jet from wall induced friction and cavitation. Waterjets made from such detached flows are called constricted waterjets and have been observed to break up in the so-called 1st wind-induced breakup regime and stay laminar even at pressures as high as 250 bars. Flow in the cone-down nozzle configuration concerning the occurrence of cavitation and hydraulic flip at operating pressure range of 10 to 200 bars have been discussed, along with their relation to hydraulic flip.
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