metacenter

/'metə,sentə/ Cách viết khác : (metacentre) /'metə,sentə/

Thân thiện

A diagram shows the metacenter of a ship's hull.

Definition

1. Noun:
   • In naval architecture and ship stability, the metacenter is a theoretical point. It is the intersection point of two imaginary vertical lines: one drawn through the center of buoyancy of a ship floating upright, and another drawn through the new center of buoyancy when the ship is tilted (heeled) by a small angle. The vertical distance between the metacenter and the ship's center of gravity is a critical measure of its initial static stability.

Usage

• The metacenter is a fundamental concept for naval architects and marine engineers. It is used to calculate and predict a vessel's tendency to return to an upright position after being tilted by an external force, such as wind or waves.
• A high metacenter relative to the center of gravity indicates greater initial stability (the ship rights itself more forcefully). A low or negative distance can indicate poor stability.

Examples

• Noun:
  • The naval architect calculated the metacenter to ensure the new design was stable.
  • A ship's stability is directly related to the height of its metacenter above its center of gravity.
  • If the metacenter falls below the center of gravity, the vessel becomes unstable and may capsize.

Advanced Usage

• Metacentric Height (GM): This is the specific term for the vertical distance between the center of gravity (G) and the metacenter (M). It is the primary numerical value used to assess initial stability.
  • A large metacentric height results in a stiff ship with a quick, sometimes uncomfortable, rolling motion.
• Transverse Metacenter: Refers to the metacenter for rolling (side-to-side) motion, which is the most common usage.
• Longitudinal Metacenter: Refers to the metacenter for pitching (fore-and-aft) motion.

Variants and Related Words

• Metacentre: The British English spelling variant of "metacenter".
• Metacentric (adjective): Relating to or involving the metacenter.
  • The metacentric height was within safe limits.
• Center of Buoyancy: The center of mass of the water displaced by the hull; a key point used to locate the metacenter.
• Center of Gravity: The point where the total weight of the ship acts; the other key point in stability calculations.

Synonyms

• There are no direct common-language synonyms for this precise technical term. Related conceptual terms include:
  • Stability point (descriptive, not technical)
  • Pivot point (in a very general, non-technical sense)

Related Phrases

• To calculate the metacenter: The standard phrase for determining this point.
  • The first step in the analysis was to calculate the metacenter.
• Metacenter above/below the center of gravity: The standard phrasing to describe the stability condition.

Học thuật

Noun

1. (shipbuilding) the point of intersection between two vertical lines, one line through the center of buoyancy of the hull of a ship in equilibrium and the other line through the center of buoyancy of the hull when the ship is inclined to one side; the distance of this intersection above the center of gravity is an indication of the stability of the ship

Từ đồng nghĩa

• metacentre