An Examination of a High Speed Liquid Jet Apparatus : About the Effect Of Convergent Nozzle on Jet

抄録

An apparatus, in which a liquid column is accelerated in a tube and a high-speed liquid jet is obtained through a convergent nozzle, is investigated. The high-speed liquid jet is obtained in a certain duration of time (velocity: 380 m/s, duration: about 1 ms), and the flow in the tube and the nozzle is calculated by the characteristic method of one dimensional flow. The main results are as follows. (1) The pressure rise at the nozzle inlet and the velocity can be determinded by the area ratio of the nozzle and the velocity of liquid close to the nozzle inlet. (2) It is obtained that pressure rise at the nozzle inlet shows an overshoot due to a transient contract flow in the nozzle, and that the rate of overshoot becomes large as the area ratio increase. (3) Corresponding to the pressure change, there occur sprays in the jet. The effect of the nozzle shape on those is shown by jet photographs.