Description
Multiply nonnegative liquidDensity by nonnegative freeSurfaceSecondMoment and divide by positive displacementMass for metacentricReduction.
Vessel draft, loading moments, and free-surface terms describe different parts of hydrostatic behavior. Their signs, reference positions, and dimensional bases must be stated before comparison.
Multiply nonnegative liquidDensity by nonnegative freeSurfaceSecondMoment and divide by positive displacementMass for metacentricReduction.
When to use this tool
Use Ballast Tank Free Surface Correction Term when you need a supplied trim, loading, or hydrostatic component.
How to use the tool and how it works
- Enter liquidDensity, freeSurfaceSecondMoment, displacementMass. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read metacentricReduction. Use the output convention below.
Multiply nonnegative liquidDensity by nonnegative freeSurfaceSecondMoment and divide by positive displacementMass for metacentricReduction.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| liquidDensity | Liquid mass density, for example kg/m³. | Required. Finite number; minimum 0. |
| freeSurfaceSecondMoment | Free-surface second moment of area, for example m⁴. | Required. Finite number; minimum 0. |
| displacementMass | Vessel displacement mass, for example kg. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| metacentricReduction | Length reduction under coherent units, for example meters. | Required. Finite number. |
{
"input": {
"liquidDensity": 1000,
"freeSurfaceSecondMoment": 20,
"displacementMass": 100000
},
"output": {
"metacentricReduction": 0.2
}
}Limitations and assumptions
- In coherent units, kg/m³ × m⁴ / kg yields meters. Geometry and loading inputs are supplied; this term alone is not a stability assessment.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Consult vessel-specific hydrostatic and stability information under the relevant loading condition for a complete assessment.
References
Similar or alternative tools
- Nautical: Cargo Tank Ullage Sounding Pair
Keep the supplied ullage or sounding and subtract it from tankHeight for the other measure.
- Nautical Draft Forward Aft Average
Average nonnegative forward and aft drafts for meanDraft and subtract forward from aft for trim.