Propeller - Optimal Pitch-Diameter
Optimal pitch-diameter ratio maximising open-water efficiency for a given advance coefficient - the basic diameter / pitch trade-off.
Optimal P/D
0.91 -
Peak η_O (approx)
0.726 -
Formula, assumptions, and limits
Wageningen B-series regression (Oosterveld-van Oossanen 1975) gives precise map. Typical merchant ship P/D 0.7–0.9, fast ferry 1.0–1.2, bollard pull 0.6.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Advance coefficient | - | V_A / (nD) | |
| Pitch-diameter ratio | - | propeller geometry |