The Analysis Of Fluid-Structure Interaction And Structural Design Method Of Cycloidal Propeller

As a special type of marine propeller,cycloidal propeller combines propulsion and steering in a single device,accurately and quickly generating infinite thrust in all directions,with excellent maneuverability and timeliness.In practical work,the interaction between flexible blades similar to cantilever beam and fluid has an important effect on the performance and blade structure of cycloidal propeller.In this paper,ANSYS is used to analyze the hydrodynamic performance and fluid structure interaction characteristics of the cycloidal propeller,and a multi-link cycloidal propeller is put forward.The size of the connecting rod which conforms to the blade oscillation law is solved by Python software,and the design scheme of the cycloidal propeller is given.The main research contents are as follows:Firstly,the working principle of the cycloidal propeller is analyzed,and the mathematical model of the theoretical motion law of the cycloidal propeller is given.The computational fluid dynamics and fluid structure interaction methods involved in the hydrodynamic and fluid structure interaction problems of the cycloidal propeller are summarized,and the variable cross-section airfoil of the cycloidal propeller is also given.Secondly,the FLUENT software is used to analyze the hydrodynamic performance,establish a suitable CFD simulation model,and verify the convergence from two aspects: the size of calculation domain and the number of grids.The hydrodynamic characteristic curve of the cycloidal propeller were obtained by exploring the different parameters and the hydrodynamic performance of the single and twin propeller cycloidal propeller.Third,two-way FSI is carried out by FLUENT+Transient structure,and appropriate FSI simulation model is established.The feasibility and accuracy of the cycloidal propeller FSI numerical computation method is verified by hydrodynamic performance comparison analysis.The variation of instantaneous deformation,stress and stress distribution with eccentricity,acceleration coefficient and position angle is studied.The effects of different materials,numbers of blades,airfoils with different sections and single-propeller and twin-propeller cycloidal propeller parameters on deformation,stress and stress distribution of cycloidal propeller blades were investigated.The mechanical characteristic curves of the blades with different parameters of the cycloidal propeller are obtained.Finally,a multi-link cycloidal propeller is proposed and a mathematical motion model of multi-link mechanism is established.Using Python software to program and calculate,a connecting rod size which conforms to the improved blade oscillation law is obtained.The hydrodynamic and fluid structure interaction numerical simulation is carried out to verify the rationality and feasibility of dimensions.The structural design scheme of multi-link cycloidal propeller is also given.It is of great significance to transition the cycloidal propeller from theory to practice.