The Study Of Jet Flow Before Propeller Affecting Propeller Behind Cross Rudder

Propeller,as the propulsion tool of submarine,is also the main source of noise when submarine is working.Propeller is the main topic of submarine research.In this paper,a new method,jet flow in front of propeller has been proposed.The effect of jet flow on the hydrodynamic performance and vibration of E1619 propeller has been studied.The specific research are as follows:1)Compared with the experimental results,the reliability of the method is verified.The hydrodynamic performance of the E1619 propeller and the integrated model of cross rudder and propeller is studied.It is found that as the speed coefficient increase,the propulsion efficiency first increases and then decreases.And it is also found that the propulsion efficiency of integrated model is lower than that of single propeller at the same speed coefficient.2)The jet device in front of the propeller is designed for the integrated model.The effects of the jet velocity,the jet angle,the position and the number of jet devices on the hydrodynamic performance are studied.The results show that with the jet velocity increase and the jet angle decrease,the propulsion efficiency increase;as the axial distance between the propeller and the jet device increase,the propulsion efficiency increase;while the transverse position of the jet device is located in the front left side and the middle of the propeller,the propulsion efficiency is significantly higher than that when the jet device is located in the front right side of the propeller;the more number of jet devices,the higher propeller propulsion efficiency.3)The effects of the jet velocity,the position and number of the jet devices on the exciting force of the propeller are studied.The results show that with the jet velocity increase,the amplitude of exciting force fluctuation increase;as the axial distance between the propeller and the jet device increase,the amplitude of exciting force fluctuation decrease;when the number of jet devices is different,compared with one or two jet devices,the fluctuation amplitude of excitation force is smaller in four jet devices.In the case of four jet devices,while the transverse position of the jet devices are located in the front and middle of the propeller,the fluctuation amplitude of the excitation force is the smallest.4)Using fluid structure interaction simulation,the exciting force,the stress and deformation of propeller under different jet velocity are studied.The results show that with the jet velocity increase,the stress and deformation of propeller increase.