The Design Of Anti-thickness Rule And Comprehensive Performance Analysis Of The Rim-electric Driven Propeller

After many years of development,the ship's propulsion system has gradually emerged a variety of new types of underwater propulsion.Among them,the electric propulsion method is one of the key problems to be solved in the electrification of the whole ship,and it has become a popular research direction.The Rim Electric-Driven Propeller is a new type of electric underwater propeller that integrates the permanent magnet motor in the catheter of the catheter paddle.It adopts the integrated structure of the blade and the motor rotor-the blade ring to drive the propeller,without the traditional Shaft connection,water lubrication and cooling through sea water.The advantages of compact structure,low vibration and noise,high power density,and flexible layout determine that the electric propeller blade ring has become a research hotspot for underwater propellers.This paper proposes a new blade thickness distribution design method suitable for blade ring electric drive propellers-anti-thickness rule design method,designed anti-thickness rule propeller,and using ANSYS-CFX and WORKBENCH platform,based on the method of solving RANS And Lowson's method are used to predict and analyze the hydrodynamic performance,strength,cavitation and noise performance of the reference and anti-thickness propellers,and verify that the anti-thickness propeller Rim Electric-Driven Propeller has better overall performance.The specific research contents are as follows:First,the influence of the gap between the duct and the blade ring and the shape of the duct on the electric propeller of the blade ring was studied.It was found that when the gap of the blade ring was 1mm,the hydrodynamic performance of the electric propeller of the blade ring was better.Four types of duct shapes were selected for calculation,and the results of comparison showed that the leading and trailing edge shapes of the duct had a greater influence on the thrust characteristics of the blade and duct respectively.The drooping form of the upper curve of the trailing edge of the duct can improve the performance of the Rim Electric-Driven Propeller.Secondly,the anti-thickness rule design method is proposed,and the anti-thickness rule propeller is designed based on Ka4-50 propellers,and the shaft is processed without shafts,and the wheel and non-wheel shaft anti-thickness rule blades are obtained.And the effect of different support methods on strength.The results show that the thrust and torque of the anti-thickness propeller with the wheel shaft are the largest,and the open water efficiency is also the highest.The anti-thickness regular propeller under the blade ring support mode can effectively improve the strength performance of the blade ring electric drive propeller.The maximum deformation area of the non-shaft anti-thickness regular propeller is smaller and has superior strength performance.Thirdly,the cavitation performance of different blades is calculated.From the comparison of cavitation distribution and cavitation thrust characteristics,it is found that the cavitation distribution of the blade ring electric drive propeller under the non-shaft anti-thickness blade is better,because there is no hub vortex,Less vorticity transmission,less energy dissipation,greater thrust,and better cavitation performance.Finally,the calculation and prediction of the cavitation-free noise of the three blades of the lower blade ring electric drive propeller were carried out.The performance of the noise was analyzed from the maximum thrust point,the highest efficiency point,the comparison between the load noise and the thickness noise,and the directivity of the sound pressure level.The total sound pressure level and sound power level of the anti-thickness regular paddle are the smallest;the load noise accounts for the main contribution to the total sound pressure level,while the anti-thickness regular paddle has a smaller load noise.The overall shape of the total sound pressure level is "8" shape,the direction of the paddle shaft is the largest,and the total sound pressure level of the paddle is the smallest in any direction,and its performance without cavitation noise is more superior.From the results of numerical calculation,the anti-thickness rule design method proposed in this paper can effectively improve the hydrodynamic performance,strength,cavitation and noise performance of the Rim Electric-Driven Propeller.