摘要
Natural and ventilated cavitations generated on a smooth-nosed axisymmetric body were studied experimentally.The characteristics of small scale and localized fluctuations of “steady cavities” were measured by pressure transducers. Comparisons between natural and ventilated cavities at different measured points for several cavitation numbers were done. It was observed that the dominant fluctuations were concentrated in the frequency range of 0Hz-50Hz for all the cavitation cases, Similar shapes and magnitudes of the frequency spectra were detected for both natural and ventilated cavities. Much larger spectral amplitude in the cavity closure region suggested al fluctuations source. From partial cavitating flow to supercavitating flow, the dominant frequency and the corresponding amplitude decreased with decreasing cavitation number, which meant that cavity became more steady while developing.
Natural and ventilated cavitations generated on a smooth-nosed axisymmetric body were studied experimentally.The characteristics of small scale and localized fluctuations of “steady cavities” were measured by pressure transducers. Comparisons between natural and ventilated cavities at different measured points for several cavitation numbers were done. It was observed that the dominant fluctuations were concentrated in the frequency range of 0Hz-50Hz for all the cavitation cases, Similar shapes and magnitudes of the frequency spectra were detected for both natural and ventilated cavities. Much larger spectral amplitude in the cavity closure region suggested al fluctuations source. From partial cavitating flow to supercavitating flow, the dominant frequency and the corresponding amplitude decreased with decreasing cavitation number, which meant that cavity became more steady while developing.
基金
Project supported by the National Natural Science Foundation of China (Grant No: 10372061) and the Doctor Founda tion (Granted No: 20030248001).
