MARITIME – HULL & NAVAL ARCHITECTURE CALCULATOR
Center Of Buoyancy
A precise tool.
What is the Center Of Buoyancy & How does it work?
The centre of buoyancy (CB) is the point through which the resultant buoyant force acts on a floating body. It is defined as the centroid of the displaced volume of water and moves with changes in the submerged shape of the hull. For a ship hull, the vertical position of the CB depends on the hull form parameters such as draft (T) and block coefficient (C_b). A higher block coefficient indicates a fuller hull, which raises the CB relative to the keel. Accurate estimation of the centre of buoyancy is essential for stability analysis, as it directly influences the metacentric height and the vessel’s righting arm. Designers use simplified empirical formulas to obtain a quick estimate during the early design stages.
z_{CB} = frac{C_b ; T}{2}
z_{CB} = vertical coordinate of the centre of buoyancy (m)
Parameters
Result
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Frequently Asked Questions
What is the center of buoyancy in a ship?
The center of buoyancy is the point where the resultant upward buoyant force acts on a floating body, typically found at the centroid of the displaced volume of water.
How does the block coefficient affect the center of buoyancy?
A higher block coefficient, indicating a fuller hull shape, raises the center of buoyancy relative to the keel.
Why is it important to know the center of buoyancy?
Knowing the center of buoyancy is crucial for stability analysis and ensuring safe navigation of ships.
How does draft influence the center of buoyancy?
The deeper the draft (the lower part of the hull that’s submerged), the higher the center of buoyancy tends to be.
Can the center of buoyancy change during navigation?
Yes, the center of buoyancy can move with changes in the ship’s load or trim, affecting its stability.
What is the relationship between the center of gravity and the center of buoyancy?
The stability of a ship depends on the relative positions of the center of gravity and the center of buoyancy; they should be as close together as possible for better stability.
How do I calculate the center of buoyancy using this calculator?
Input the draft (T) and block coefficient (C_b) into the calculator to determine the vertical position of the center of buoyancy.
Results are for informational purposes only and do not constitute professional advice.