HZノズルの振動特性 : 実船実験

抄録

In order to improve the propulsive efficiency of a ship, HZ nozzle installed just in front of a propeller has been developed. In this paper, vibration characteristics of HZ nozzle have been investigated by full scale experiments and FEM analysis. The results obtained are as follows; 1) There are two basical vibration modes which are symmetrical and asymmetrical, and the difference of the natural frequency between them is about 10%. 2) Coupled effect of rudder and shoe piece is negligible. 3) The natural frequency of HZ nozzle in water is reduced to about 55% of that in air. 4) A simplified formula which is convcnient for the design of HZ nozzle, gives a good estimation of the natural frequency of HZ nozzle.