Manoeuvring Data Dialog - Hydrodynamic Derivatives Tab
- Last UpdatedDec 18, 2025
- 1 minute read
All of the manoeuvring calculations require the input of propeller information, namely the number of propellers, number of blades and diameter.
In addition, the mean pitch and blade area ratio are also required.
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Number of Props |
Number of propellers (see limits below). |
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Number of Blades |
Number of blades on each propeller (see limits below). |
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Diameter |
Propeller diameter (see limits below). |
|
Powering Values |
If powering calculations for this loading condition have previously been performed, then you may select this option to use the pitch and blade area ratio calculated for the optimum propeller. |
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User Input |
If no powering calculations have been performed, or if you require a different pitch and/or blade area ratio this option should be selected. |
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Mean Pitch |
Mean propeller pitch (see limits on pitch ratio (P/D below). |
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Blade Area Ratio |
Blade area ratio. |
Depending on ship type as specified on the Main Particulars dialog, the following limits are applied to the input data:
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Minimum Value |
Maximum Value |
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|---|---|---|---|
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Limits for Naval Ships |
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No. of Propellers |
1 |
2 |
|
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Propeller Diameter |
- |
0.7*(Mean Draft+Trim) |
|
|
Pitch/Diameter |
0.50 |
||
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No. of Blades |
2 |
1.40 |
|
|
Blade Area Ratio |
0.30 |
1.05 |
|
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Limits for Merchant Ships |
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Number of Propellers |
1 |
4 |
|
|
No. of Blades |
3 |
5 |
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