Bulbous bow is a projecting globule situated at the bow of a ship just underneath the waterline. Bulbous bow reduces the hull wave making resistance of a ship, which is the major residuary frictional resistance of the ship.
Advantages
> Increase propulsion efficiency
> Increase fuel efficiency
> Increase ship speed
> Increase stability
> Reduce dragging
> Reduce fuel consumption
> Reduce pitching
> Act as BUMPER in collision.
When the water is cut by the bulbous bow, mainly two types of waves are formed ; primary wave and secondary wave. The primary wave formed by the bow, just in front of the bow cuts the secondary wave formed by the ship hull, thereby reducing drag.
Construction
> Floors are fitted at every frame space in the bulb when bulb is large
> Transverse are fitted at about every fifth frame in long bulbs
> Smaller bulbs have centerline web
> All bulbous bow horizontal diaphragms are fitted
> Shell plating covering bulb has increased shell plating
> Increase propulsion efficiency
> Increase fuel efficiency
> Increase ship speed
> Increase stability
> Reduce dragging
> Reduce fuel consumption
> Reduce pitching
> Act as BUMPER in collision.
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