Minimum blade-area ratio A_E/A_0 to avoid cavitation per Keller formula - the screening calculation for propeller sizing given thrust and shaft depth.
Formula
$$ A_E/A_0 \geq \frac{(1.3 + 0.3Z)T}{(p_0 - p_v)D^2} + K $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $T$ | Thrust | N | powering calc |
| $D$ | Propeller diameter | m | prop geometry |
| $p_0 - p_v$ | Atmospheric + hydrostatic − vapour pressure | Pa | hydrostatics |
| $K$ | Keller constant | - | Keller (1966) |
Sources
- Keller J. - RINA 1966.