Abstract
In the present study, we focused on the length of the tip cavitation as a parameter of cavitation in order to investigate the thermodynamic effect on a cavitating inducer. Comparison of the tip cavity length in liquid nitrogen (76K and 80K) with that in cold water (296K) allowed us to estimate the strength of the thermodynamic effect. Sub-synchronous rotating cavitation appeared both in liquid nitrogen and in cold water. To the contrary, cavitation surge occurred only in cold water at lower cavitation numbers. It was inferred that the thermodynamic effect decreases mass flow gain factor M at lower cavitation numbers when the cavity length develops over the throat, and that its effect suppresses the cavitation surge in liquid nitrogen.
