Cavitation Nuclei Size Distribution in High-Speed Water Tunnel Under Cavitation and Non-Cavitation Conditions.

摘要

Gas nuclei spectra measurements obtained with our modified Coulter Counter system in cavitating and non-cavitating conditions in our High Speed Water Tunnel are reported. These show the strong dimunition with time of nuclei population during runs of several days,presumably as the gas is continually forced into solution. Total gas content during these runs is held approximately constant. The general shape of the spectra curves then remains approximately constant with time,although strongly diminishing in amplitude. It can be predicted by a quasi-theoretical expression which does not include any empirical constants. Hence its applicability to tunnel flows may be quite general. The effect of cavitation to the same tunnel velocity is to reduce nuclei content more rapidly than in its absence,even though mean tunnel pressure is less in the cavitating case.