液体急加速時のキャビテーション発生条件

抄録

This study investigates general criterion of cavitation occurrence at a sudden acceleration of a liquid. We conduct an experiment as follows: A test tube filled with a liquid falls and hits a floor. The liquid is accelerated quickly and negative pressure is generated inside the liquid. When the negative pressure is large enough, cavitation can happen. In previous study, Ca number is proposed as a cavitation criterion for explaining experimental results installing a SS400 floor. In our preliminary experiments installing an ABS floor, however, results disagree with Ca number. It suggests unsuitable expression of pressure inside the liquid in Ca number. Therefore, this study aims to reformulate Ca number applicable for various floors. We measure acceleration of the test tube time by an acceleration sensor and estimate pressure fluctuation in the liquid. The reformulated number Ca∗ agree well with cavitation criteria for both floors.