Experimental studies of water entrance in axisymmetric bodies with a negative pressure gradient

A series of water entrance tests for different special axisymmetric bodies with the negative pressure gradients along the surface was carried out and different flow patterns were revealed. In particular, for the smaller velocities, the flow without a cavity takes place. Increasing the entrance velocity leads to the typical non-steady super cavity flow. The body shape influences significantly the critical entrance velocity at which the flow pattern changes. In particular, an example of a slender body showed the flow pattern without a cavity for the whole range of the available entrance velocities (up to 6 m/s).