Steady hydrodynamic performance simulation of integrative energy-saving propulsion system

In order to effectively study energy saving efficient integrative energy-saving propulsion systems, the computational fluid dynamics (CFD) method was used. The CFD method allows the numerical simulation of the steady hydrodynamic performance of the common propeller-rudder system and integrative energy-saving propulsion system. A sub-domains mesh partition method was adopted, and the computation domain was separated into two sub-domains, in which screw propeller was included and hexahedral elements were used in all domains. The mesh was locally refined on the propeller surface and near the wake flow field. Hydrodynamic performance parameters such as thrust coefficients, torque coefficients and efficiency were calculated and compared with the results of potential flow methods and experimental data. The results showed that numerical results agreed well with the other two results, which validated the reliability of the numerical method. At the same time, the hydrodynamic performance and surface pressure distribution of the two propulsion systems were examined. It can be concluded that the efficiency of integrative energy-saving propulsion systems which had 3%~8% increment was improved through increasing propeller thrust and reducing rudder drag. In comparison with the pressure distribution of common rudder, the area of pressure focus domain was reduced in leading side of design rudder, the pressure distribution of rudder center was changed with more uniformity, and the pressure coefficient of the rudder section was more flat, thus, making the hydrodynamic performance of design rudder more ameliorated.