Performance improvement of ship propulsion equipment driven by high-pressure gas (Effect of the device with which an actuator was equipped)

• Published in: Nihon Kikai Gakkai rombunshuu. B hen Vol. 61; no. 590; pp. 3728 - 3734
• Main Authors: Sakamoto, Masahiko, Tsutahara, Michihisa, Kimura, Takeyoshi
• Format: Journal Article
• Language: Japanese
• Published: 01.01.1995
• Subjects: Actuators; Bubbles (in fluids); Flow of water; Jets; Nozzles; Two phase flow
• ISSN: 0387-5016

We describe here an experimental study of a new type of nozzle which generates a high-speed two-phase water jet as a propulsion device for a ship. In order to investigate performance improvement of this nozzle, two types of the improved device were proposed. The first type has the same structure as that of an axially symmetrical nozzle equipped with propeller and turbine. The second type has a cap of U-shaped cross section in front of the two-dimensional nozzle without bottom. These devices were set in a towing tank, and thrust was measured for various parameters such as air injection angle, pressure of injection gas, and towing speed. The thrusts of these two types of device increase as compared with those of the original type. The maximum propulsion efficiency is about 20% at the flow velocity of 1.5 m/s. It was proven that the two types of actuators improve the performance of this device.