Research On Hydrodynamic Performance Of The Oscillating Foil Based On Weis-Fogh Effect

In recent years,with the development and application of Bionics,it becomes a hot issue,bionic ship propulsion are given more and more research and attention.Bionic propulsion is no longer limited to imitate the swimming mode and body structure of aquatic organisms,is also imitate the principles of flight of winged insects.Weis-Fogh agency is a simulation of insect flight and can be used in bionic ship propulsion.The lift mechanism of agency is different from propeller,It attracts wide attentions because of it can instantly get high lift and good flexibility.Therefore,theoretical research of the Weis-Fogh agency and analysis of its hydrodynamic characteristics are great significance for the development and application of new bionic propulsion.It presents a propulsion that imitates the Weis-Fogh agency-WF hydrofoil,it is made of oscillating foil and bezel.Its hydrodynamic characteristics are calculated and analyzed by using CFD methods.First,Gambit software is used to build a physical model of WF hydrofoil using a vane airfoil NACA0012,using structured and unstructured grids to divide calculating watershed.Using Fluent software to calculate the model with dynamic mesh and analyze the hydrodynamic performance,including pressure distribution and tail vortex case around the WF hydrofoil.Analyze the influence of motion parameters of WF hydrofoil about propulsive performance.And verify the feasibility of the calculation method.Secondly,numerically calculate the movement of the oscillating foil without bezel with same regular pattern,analyze and compare the propulsive performance of WF hydrofoil.By analyzing the picture of pressure distribution and vorticity,confirm a similar effect of Weis-Fogh agency in the movement of WF hydrofoil,and analyze the influence of the similar effect about propulsive performance of WF hydrofoil.Finally,numerically calculate flow field about the symmetrical swing of two WF hydrofoil at the behind of ship,calculate the hydrodynamic performance and compare with two oscillating foil without ship,analyze pressure distribution and tail vortex case,to confirm the similar effect of Weis-Fogh that is formed when two WF hydrofoil swing after ship is beneficial to the propulsive performance.