η_D = η_O · η_H · η_R - the efficiency of energy transmission from delivered power to effective (towing) power.
Formula
$$ \eta_D = \eta_O \cdot \eta_H \cdot \eta_R $$Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $\eta_O$ | Open-water efficiency | - | open-water chart |
| $\eta_H$ | Hull efficiency | - | hull efficiency calc |
| $\eta_R$ | Relative rotative efficiency | - | typical 0.95–1.05 |
| $\eta_D$ | Quasi-propulsive coefficient | - | result |
Sources
- SNAME PNA Vol II.