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Cavitation is one of the major problems in the development of rocket engines. There have been few experimental studies to visualize cryogenic foil cavitation. Therefore a new cryogenic cavitation tunnel of blowdown type was built. The foil shape is “plano-convex”. This profile was chosen because of simplicity, but also of being similar to the one for a rocket inducer impeller. Working fluids were water at room temperature, hot water and liquid nitrogen. In case of Angle of Attack (AOA)=8°, periodical cavity departure was observed in the experiments of both water at 90℃ and nitrogen at -190℃ under the same velocity 10 m/sec and the same cavitation number 0.7. The frequencies were observed to be 110 and 90 Hz, respectively, and almost coincided with those of vortex shedding from the foil. Temperature depression due to the thermodynamic effect was confirmed in both experiment and simulation especially in the cryogenic cavitation.
There are been few experimental studies to visualize cryogenic foil cavitation. Thus a new cryogenic cavitation tunnel of blowdown type was built. The foil shape is “plano-convex ”. This profile was chosen because of simplicity, but also of being being similar to the one for rocket inducer impeller. Working fluids were water at room temperature, hot water and liquid nitrogen. In case of Angle of Attack (AOA) = 8 °, periodical cavity departure was observed in the experiments of both water at 90 ° C and nitrogen at -190 ° C under the same velocity of 10 m / sec and the same cavitation number of 0.7. The frequencies were observed to be 110 and 90 Hz, respectively, and almost coincided with those of vortex shedding from the foil. Temperature depression due to the thermodynamic effect was confirmed in both experiment and simulation especially in the cryogenic cavitation.