Design Of Power Saving Device For Mega Yacht

The energy saving of ships has become a worldwide important issue in shipindustry.Among the available solutions,installing power saving device,which is themost convenient way to construct,has significant energy saving effect.To mega yachtsor high speed displacement ships,improving propulsion performance is a major task ofthe rapidity.In this paper,based on the prototype of a mega yacht,the appropriate powersaving devices are designed to improve propulsion performance.Based on ship propulsion theory,the paper analyzed power-saving device andclarified the basic design concept.Two kinds of innovative power saving devices wereprovided.Based on pre-turning current theory, power-saving shaft strut wasdiscussed.Combined the characteristics of twin skeg with cochlea-channeled stern,thetwisted shaft bossing suitable for outward rotating propeller was brought forward.The paper discussed the solution of the RANS equation in3D flow field with CFDsoftware.By CFD pre-processor,the hybrid mesh was generated with the partitionedpropeller flow field. Then the propeller performance in the unsteady flow field issimulated with multiple reference frame and sliding mesh.To verify the efficiency of proposed methods,the concrete designs were given outfor the prototype.The3D models were established while the meshes were set up for thenumerical simulation of wake stream field.The characteristics of wake stream field werefound which demonstrated the efficiency of the devices.Based on the designs,a ship model experiment was carried out.With the analyzingof experimental data,the validity of designs were confirmed while the qualitative effectof each device were discussed.Finally the paper summarized the whole work andenvisioned future study of the details and assumptions.