Detection of Incipient Cavitationin Cavitating Liquid Jet Apparatus with an Accelerometer and Its Application to Orifice Cavitation

In general, cavitation is an undesirable phenomenon in many cases. In order to prevent from cavitation which produces great damage in the valves and piping system of power plants, it is necessary to detect the occurrence of cavitation. In order to determine the initial stage of cavitation process, an accelerometer was used to establish the technique of estimating the incipient cavitation number by impact signals. On the other hand, in many cases, cavitation number in orifice part is defined with the average flow velocity, however, the definition with upstream and downstream pressure of flow is more useful. Therefore, the incipient cavitation number defined in general way by using a cavitating jet method was clarified and was extended to regular orifice cavitation.