| With the gradual depletion of land resources,the development of marine resources development quickly,diving depth is increasing.These need to be more flexible underwater work,thus need some precise positioning in these platforms work,and requires good maneuverability.Cycloidal propeller thrust as the flexibility to control the size and direction of the propeller to get attention.Moreover,cycloidal propeller can be used for special military vessels required to have good stealth performance,so the noise performance of cycloidal propulsion is also being concern.This paper uses CFD numerical simulation and modeling technology of hydrodynamic performance and noise performance cycloidal propeller were studied and compared the results of the calculated and experimental values.This paper first describes the cycloidal propulsion development process,outlined cycloidal propulsion works and summarized the cycloidal propeller hydrodynamic performance trends of theoretical research and experimental research at home and abroad.Based on the parent ship designed cycloidal propeller,according to the mother vessels and equipment designed to test experimental models and in Shanghai Ship and Shipping Research Institute conducted a test based on the noise.Establish numerical model based software FLUENT,the mesh use structured grid method in order to increase the efficiency.Calculations were selected standard k-?,RNG k-? nd Reynolds stress turbulence model equations in three separate calculations are calculated to promote the characteristics of the eccentric angle is 0 °.By comparison with the experimental results,obtained that using a numerical model to calculate the Reynolds stress equations are more accurate,thus more suitable for cycloidal propulsion calculator hydrodynamic characteristics.Simulation cycloidal propulsion hydrodynamic performance using Reynolds equation,the calculated and experimental work conditions consistent.The paper calculates eccentric angle 0 °,30 ° and 60 ° of the situation.The results obtained cycloidal propeller thrust,torque,lateral force and efficiency,as well as variation of blade thrust and torque.When the cycloidal propeller eccentric angle is 0 °,the lateral force is negligible small,suitable for direct shipping case.By changing the size of the eccentric angle can change the direction of the ship,the bigger the change in direction of the eccentric angle of the stronger.In the propeller efficiency,cycloidal propeller efficiency can reach up to 0.6 above,as the level of propellerefficiency.Based on broad FW-H equation combines the sound field and the flow field,using FLUENT software modules for acoustic noise performance cycloidal propeller numerical model numerical calculation,got the results of cycloidal propeller hydrodynamic noise in different conditions and the results of sound pressure pulsation,sound pressure level and the total sound level results,and got that behind the cycloidal propeller noise is smaller than the eccentric sidefor about 1-2 dB.Mechanism based on noise analysis,design the cycloidal propeller blade on the bottom of a numerical model of the end plate,the use of this model to simulate the noise,and the calculated results without side panels contrast,leaves a little to get the dress of the end plate can reduce hydrodynamic noise conclusions maximum reduction of up to 1.18 db.Analysis of the mechanism of hydrodynamic noise,combined with the propeller noise model test method,test methods proposed noise model is applicable to cycloidal propeller,and tested.The experimental results in terms of the actual ship results,feed speed of cycloidal propeller noise performance at the eccentricity of 0.4 to 0.6 and 6kn work situations.The result is lower than propeller about 0.5 to 2 db.As can be seen from the experimental results,under the same forward speed coefficient,the eccentricity increases,the pusher total sound level is reduced,which is consistent with the simulation results. |
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