EFD and CFD capability assessment for KCS added power (AP) in head and oblique waves are conducted based on experiments from three facilities using three different model sizes and CFD from five institutes. The analysis includes the standard deviation (SD) in both CFD and EFD to identify facility biases, scale effects and CFD errors for motions, self-propulsion (SP), propulsive efficiency (η) and AP. The overall SD%D (D: EFD values) for all calm water SP variables and AP variables is 9% and 11%, respectively. SP correlates with Re via advance coefficient J(Re) and SP points lie along nondimensional propeller load curves. AP vs. λ/L correlates with large bow relative motion such that the wave effects on J(λ/L) have the same scaling as the model size effect J(Re). Logarithmic derivative analysis of EFD data shows that for head waves the added resistance (AR) and η are responsible for 70 vs. 30%AP, respectively, whereas for oblique waves the AR and η are responsible for 55 vs. 38%AP, respectively. The overall conclusion is that the experimental and CFD approaches are of sufficient accuracy to be useful for design.
