  The concept of Hydrodynamic Cavitation (HC) has emerged as a promising method
for wastewater treatment, bio-diesel production and multiple other
environmental processes with Venturi-type cavitation reactors showing
particular advantages. However, numerical simulations of a venturi-type reactor
with an elucidated explanation of the underlying flow physics remain
inadequate. The present study numerically investigates and analyzes the flow
inside a venturi-type reactor from both global cavity dynamics and localized
turbulence statistics perspectives. Some models in the Detached Eddy Simulation
(DES) family are employed to model the turbulence with the study initially
comparing 2D simulations before extending the analysis to 3D simulations. The
results show that while URANS models show significantly different dynamics as a
result of grid refinement, the DES models show standard flow dynamics
associated with cavitating flows. Nevertheless, signifi- cant discrepancies
continue to exist when comparing the turbulence statistics on the local scale.
As the discussion extends to 3D calculations, the DES models are able to well
predict the turbulence phenomena at the local scale and reveal some new
insights regarding the role of baroclinic torque into the cavitation-vortex
interaction.The findings of this study thus contribute to the fundamental
understandings of the venturi-type reactor.
