Wake-adapted design of fixed guide vane type energy saving device for marine propeller

A wake-adapted design method of downstream fixed guide vanes (FGV) for marine propeller is proposed based on propeller vortex theory (PVT) and surface panel method (SPM). The FGV is designed to recover the slipstream rotational energy of propeller into an additional thrust. The hydrodynamic interaction between the propeller and the FGV is the key point in the combined propulsor design and is considered through induced velocities calculated by SPM. As the guide vanes are fixed and work in nonuniform wake field, different blades have significantly different inflow velocities. Therefore, the blades of FGV ought to be designed independently. The radial circulation distributions of the combined propulsor as well as the tangential induced velocities in the slipstream are calculated to validate the energy saving principle of FGV. The results of design case study indicate that the FGV after propeller can recover the slipstream rotational energy of propeller effectively.