The research reported in this paper has been carried out to investigate the effect of large bulbous bows on the resistance and propulsion of a ship. The basic shape of the investigated bulbs was a sphere, connected to the ship in such a way that the original hull form was maintained as much as possible.
The basic ship was a fast cargo liner of 150 m (500 ft) length. Her trial speed corresponds to about . The application of a bulb of conventional size and shape would not favourably affect the resistance in the speed range of interest. The application of a bulb based on a big sphere, however, did reduce the required power at equal speeds. For the ship under consideration this reduction was 8.9 per cent. at .
The size of the sphere, needed to reduce the bow wave system as much as possible, was determined by a simple approximative theory. The experiments concerned in the first instance the location of the sphere relative to the bow, the effect of a variation of the diameter of the sphere and of the angle of entrance of the water lines of the ship.
When the ship was fitted with a large bulb faired into a more conventional shape, the resistance curve of the ship obtained the character of that of a ship one or two knots faster than the basic ship.
Finally the effect of a bulbous bow was compared with the effect of small changes in the main dimensions of the ship.
Research on bulbous bow ships1
Part I.A. Still water investigations into bulbous bow forms for a fast cargo liner
International Shipbuilding Progress ; 13 , 142 ; 163-180
1966-06-01
18 pages
Article (Journal)
Electronic Resource
English
Research on bulbous bow ships1
IOS Press | 1966
|Research on bulbous bow ships1
IOS Press | 1966
|Research on bulbous bow ships -- 1.A
Engineering Index Backfile | 1966
|Research on bulbous bow ships1
IOS Press | 1965
|Research on bulbous bow ships -- 2A
Engineering Index Backfile | 1965
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