抄録
In this investigation, pressure fluctuations in an inducer were observed in order to examine the characteristics of unsteady cavitation at lower cavitation coefficients. From the spectrum analysis, it was confirmed that the pressure fluctuations occurred with the frequency of 0.6× ωs (ωs, shaft rotational frequency), 1.0×ωs, 1.1∼ 1.3×ωs and also 2.1×ωs. The 0.6×ωs was caused by the rotating phenomena in an inducer rotational direction. The 1.1∼ 1.3×ωs was caused by the super-synchronous rotating cavitation. The 2.1×ωs was caused by rotating cavitation in the counter direction. In addition, the amount of head reduction of the inducer caused by the synchronous cavitation (1.0×ωs) depended on the cavity pattern of the blades.
