Noise generated by cavitating single-hole and multi-hole orifices in a water pipe

摘要: This paper presents an experimental study of the acoustical effects cavitation caused by a water flow through orifice. A circular-centered single-hole orifice and multi-hole are tested. Experiments performed under industrial conditions: pressure drop across varies from 3 to 30 bar, corresponding numbers 0.74 0.03. Two regimes discerned. In each regime, broadband noise spectra obtained far downstream presented. nondimensional representation is proposed: in intermediate ‘developed cavitation’ collapse reasonably well; more intense ‘super depend strongly on quantity air remaining orifice, which revealed measure speed sound at transducers. whistling associated with periodic vortex shedding observed. The Strouhal number agrees well literature for single-phase flows. 'super disappears.