Multi-Objective Evolutionary Optimization Technique Applied to Propeller Design

Multi-objective functions of the propeller blade optimization are always regarded as important aspects of propeller design. This paper particularly presents a computational method to estimate the hydrodynamic performances including minimum cavitation, highest efficiency, and acceptable blade strength. The included parameters are as well, the number of blades, chord length, thickness, camber, pitch, diameter and skew. We also discuss the effect of the skew on the propeller performance and extract a formulation for these propose. In the optimization process, the evolution strategy (ES) technique is linked to the computational method to obtain an optimum blade. In order to allow the large variation of blade form during optimization process, the propeller section is represented by NURBS. New propeller forms are also obtained from the well-known B-series and DTRC are taken as initial forms in the optimization process at design speed of typical ships. The benchmark results for the two test cases prove the designed optimum propeller to be acceptable.