Atomization and Sprays, Vol.9, No.4, 419-429, 1999
Turbulence under quasi-cavitating conditions: A new species?
This article presents measurements of turbulence fluctuations in an upscaled, two-dimensional model of a plain-orifice injector,,with and,without the presence of cavitation simulated by an air bubble. The measurements were made at different locations in the orifice cross section, and at different planes along the direction of the flow. Two-color laser Doppler velocimetry data allowed the calculation of Reynolds stresses as roell as turbulence power spectra. The results show that the turbulence in the presence of simulated or quasi-cavitation behaves quite differently from the case without cavitation: it changes more radically with changes on the Reynolds number and seems to be fairly independent of the magnitude of the Reynolds stresses. These observations cannot be explained by using conventional shear-induced turbulence models. Experiments with forced cavity fluctuations show an increased receptivity at certain frequencies.