Underwater craft such as torpedo with boundary layer control device

摘要

The craft (10) has a device for creating a boundary layer which reduces the drag between the craft and the surrounding water. The device takes the form of a thrust nozzle (12).The nozzle may also act simultaneously to propel the craft, and may have an annular throat which adapts independently to the ambient pressure of the water. It may also be divided into individual separate nozzles which are arranged around the circumference of the craft and which may be connected to individual fluid channels. The nozzle may be arranged at the hull position which has the maximum cross-sectional diameter.