TOTAL PRESSURE LOSS REDUCING METHOD AND DEVICE FOR INTAKE PART FOR WATER JET PROPULSION MACHINE

摘要

PURPOSE: To reduce a total pressure loss by thinning a thickness of a boundary layer of an intake part. ;CONSTITUTION: A wall of an intake 2 part of an intake duct 1 is formed as a duplex tube structure composed of an inner tube part 10 and an outer tube part 11. A large number holes 12 are arranged in the inner tube part 10, and the inside of the intake duct 1 and a chamber 13 are communicated with each other through the holes 12. The chamber 13 and a part of an outlet side delivery nozzle 3 of the intake duct 1 are connected to each other by a conduit 14, and fluid is sucked through the inside of the chamber 13 by using a pressure difference in a negative pressure part of a delivery nozzle 3 part. Flow speed of the fluid flowing along the inner tube part 10 is increased by sucking out the fluid slowly flowing by a boundary layer created on an inner wall surface of the inner tube part 10 to the chamber 13 through the holes 12.;COPYRIGHT: (C)1995,JPO