Abstract: Time average pressure and frequency spectrum of the flow behind multi-orifice plates have been
measured using a data acquisition system of SINOCERA-YE6263 for a hydrodynamic cavitation reactor
designed in the Hydraulics Laboratory, ZheJiang University of Technology. The study focuses on the effects
of shape, size, spacing, and pattern of the orifices on pressure downstream of the plate. The results show that
a quincunx pattern of orifices restrains effectively the pressure recovery while the shape of orifice opening
has little effect on the time average pressure. The power spectrum of pressure fluctuations depends on the
opening size, spacing, and pattern of orifices.