抄録
The authors investigated on the performance of the water jet ship by blowing air into the nozzle in former papers but there was the limit by lowing only air. In this study, the method of intermittent blowing of the high-pressure air was investigated to obtain more thrust. More water was included into the nozzle by making outflow of air intermittently and the average density of fluid increases. The result showed that the thrust increased about more than 60% in comparison with the conventional method. It was confirmed that the flow of the outflow inside the nozzle waved and flowed periodically by the use of the motion scope camera.