|
ABSTRACT
This thesis is aimed at designing a propeller which is
outstanding in performance, to serve as a parent
model of a new series for high speed patrol boats. A new
design procedure and philisophy is estabilished to design the
so- called new-section propeller. It is different from the
method used for conventional NACA a=0.8 section.
For the propeller of high speed craft , the performance
of the new-section prepeller is measured at different cavitation
numbers at the inclined shaft condition, and compared with that
of Newton- Rader propeller. The experimental results
show that both the efficiency of the new-section propeller
and the cavitation extension on blade are better than
those of the Newton-Rader propeller at the inclined shaft
condition regardless cavitation numbers. For propeller of
container ship, one of the most important issues is the
reduction of pressure fluctuation induced by a cavitating
propeller. Similarly, a design procedure and philisophy which
takes account of strength problem of blade due to high
skew is estabilished to design new-section
propellers. The results of experiment and calculation also show
that both the cavitation volume and the pressure
fluctuation on ship stern induced by new- section
propeller are much lower than those of NACA propeller.
|