A comprehensive design method is applied to design of counter-rotating propellers (CRP). A numerical nonlinear optimization algorithm is first used for design of each propeller. This approach represents a blade by B-spline geometry and the design variables at the location of the vertices of the B-spline polygon determine the optimal blade shape. The nonlinear optimization method aims at minimizing the torque for a given target thrust with constraints, e.g. the minimum pressure constraint for a fully wetted propeller or maximum allowed cavity area for a cavitating propeller. Then the interaction of the designed propellers and a given pod including the viscous flow field around the two propellers is analyzed by coupling a vortex-lattice method (VLM) with a Reynolds-Averaged Navier-Stokes (RANS) solver. The analysis determines a new inflow for a new design of propellers. The procedure of the design and interaction analysis finishes when the propeller thrust converges within a certain tolerance. Finally, the designed propellers are compared with the original propellers.

Keywords:
optimization problem, comprehensive design method, geometry, naval architect, design method, effective wake, design variable, forward propeller, texas texas section, thrust
This content is only available via PDF.
Copyright 2022, The Society of Naval Architects and Marine Engineers
You can access this article if you purchase or spend a download.