Research On The Integrative Energy-Saving Propulsion System Of The Propeller-rudder Bubble-twisted Rudder

The sectional hydrodynamic energy-saving propulsion system device is a new type of hydrodynamic energy-saving device,which can make full use of the favorable interaction coming from diverse hydrodynamic devices,and the energy-saving effect of the sectional hydrodynamic one is often greater than the single one.The integrative energy-saving propulsion system is a one of them whose energy saving capacity is based on optimizing the interaction between the vessel’s propeller and rudder.The new propulsion system is equipped with a rudder ball to perfect the propeller’s wake-field,which can make an improvement of the propeller’s efficiency.The leading edge of the rudder is twisted to recycle the energy of the propeller’s wake-field and increase the additional thrust of rudder.By rational refitting the rudder of integrative energy-saving propulsion system,it can produces better hydrodynamic performance and keep a better maneuverability,so the integrative energy-saving propulsion system is economic and owning remarkable energy-saving effect.The integrative energy-saving propulsion system was designed based on panel method on the condition that whether there is side flow.(1)On the condition of no wake fraction: On the base of the given propulsion system of the propeller-rudder and the propulsion system of the propeller-rudder bubble-rudder,The paper analysis the oscillation of the rudder thickness ratio and the ratio of rudder bubble diameter and propeller diameter to the propeller-rudder bubble-rudder hydrodynamic performance,And introduced an optimization design method for the propeller-rudder bubble-rudder propulsion system.the panel method of making twist rudder to produce additional thrust of rudder as much as possible was discussed,and forming the propulsion system of the propeller-rudder bubble-twisted rudder,and hydrodynamic performance of the new propulsion system is calculated,and the result of it is used to make comparison with the hydrodynamic performance of the optimized system of the propeller-rudder bubble-rudder,assuring the design of the twist-rudder is reasonable.(2)On the condition of the wake fraction: Firstly,the paper will get the axial wake fraction of one KCS ship model through the hydrodynamic performance of the numerical simulation.Then the paper selected the propulsion system of the propeller-rudder and the propulsion system of the propeller-rudder bubble-rudder according to the above method(1).The paper analysis the oscillation of the rudder thickness ratio and the ratio of rudder bubble diameter and propeller diameter to the propeller-rudder bubble-rudder hydrodynamic performance,and introduced an optimization design method for the propeller-rudder bubble-rudder propulsion system.the panel method of making twist rudder to produce additional thrust of rudder as much as possible was discussed,and forming the propulsion system of the propeller-rudder bubble-twisted rudder,and hydrodynamic performance of the new propulsion system is calculated,and the result of it is used to make comparison with the hydrodynamic performance of the optimized system of the propeller-rudder bubble-rudder,assuring the design of the twist-rudder is reasonable.