Numerical modelling of the hydrodynamic performance of sinusoidally pitching hydrofoils

The collective and cyclic pitch propeller (CCPP) is a novel efficient and effective propulsion and manoeuvring alternative for Autonomous Underwater Vehicles (AUVs). A two-dimensional numerical model was developed to investigate the hydrodynamic performance of the CCPP, simplifying the three-dimensional CCPP’s blade operation to that of two-dimensional pitching hydrofoils. The hydrodynamic performance of the hydrofoils was defined by the degree of asymmetry and unsteady evolution of the generated forces over the azimuthal cycle, identified in earlier CCPP research as key in the control of the resulting manoeuvring forces and AUV motion. The model development established a numerically efficient and space-time independent solution procedure and validated the model’s ability to predict the effects of parametric pitch variations on the azimuthal asymmetry of the generated forces.