Penetration of a solid layer by a liquid jet

The resistance of a solid layer to penetration by a liquid jet has been calculated for a variety of target geometries and in both the high and low jet-velocity régimes. The theory is applied to the penetration of an aluminium layer by a water jet and a uranium dioxide layer by a sodium jet. It is thought that the violent interaction that may occur when a hot liquid (fuel) comes into contact with a cold vaporizable liquid (coolant) is due, in part, to penetration of the fuel by jets of liquid coolant, and the results presented here indicate that the thickness of the solid layer to be expected on the fuel is not an insurmountable barrier to jet penetration of the liquid fuel.