Numerical Analysis And Experimental Design Of Single Degree Of Freedom Flexible Flapping Foil

The development of underwater propellers has gone through thousands of years of continuous evolution and evolution.At present,in the field of ship propulsion and propulsion devices of underwater vehicles,most of them are traditional propeller propellers with mature technology,but there are still some shortcomings.Compared with the transmission system of the propeller,the bionic flapping-foil’s mechanism is simpler and less noisy.The maneuverability of the flapping-foil is more flexible than that of the traditional propeller,and it can freely realize small-scale steering in the water.And it also has certain advantages over the propeller propulsion in terms of environmental friendliness.Therefore,the research on bionic propulsion with flapping-foil is of great significance to improve the propulsion system of ships and underwater vehicles in the field of propulsion research.This subject continues to explore and study on the basis of the previous research on the propulsion of the flapping-foil conducted by the research group.On the basis of the previous research on the rigid foil,the flexibility of the flapping-foil is introduced as an important parameter affecting the propulsion characteristics.The research content involves the flexibility of the flapping-foil,which needs to consider the fluid solid interaction.It is different from the previous numerical methods used in the rigid foil,and the calculation is often not convergent due to the influence of many factors in the fluid solid coupling calculation.Therefore,the fluid structure coupling numerical calculation based on the ANSYS Workbench platform has comprehensively sorted out a set of numerical methods suitable for the study of the flexible flapping-foil,including the mesh method to solve the mesh distortion caused by motion deformation and the solution to improve the convergence of coupling iteration.Based on the above numerical methods,for the single degree of freedom flexible flapping-foil with pure pitch and pure heave motion,starting from the three aspects of flow characteristics,material properties and motion properties,this paper selects representative parameters Strouhal number,stiffness coefficient and motion amplitude to study,discusses the influence of these parameters on propulsion characteristics,and obtains a better efficiency range within the range of calculation conditions.Finally,for the hydrodynamic experiment of the pure heave flapping-foil,the motion drive of the flapping-foil experimental frame of the research group is designed to enable it to move sinusoidally,the scheme design of the influence of the inertia force is carried out,and the measurement progress is increased.Finally,the stability of the partial connection of the experimental frame is optimized.