Numerical Calculation And Experimental Study On Hydrodynamic Performance Of Oscillating Hydrofoil

Airfoil / hydrofoil has a very wide range of engineering applications as a very important power or energy saving device infrastructure in the field of warship and aeronautics.Studying hydrofoil performance of airfoils / hydrofoils can provide a more direct-reference basis,which is also a hot spot of research scholars at domestic and abroad.Based on the bionics design concept,this paper applies many biological characteristics to the structural optimization of hydrofoils,designs three-dimensional hydrofoils with different leading edge structures.Studying the hydrodynamic performance of three-dimensional hydrofoils under unsteady conditions provides a novel idea for the research and design of airfoils in the engineering field.In the process of the research,the hydrodynamic performance of two-dimensional airfoils in unsteady state is studied first,and the unsteady conditions are classified into the pitching motion,heaving motion,the coupling states of pitch and heave.The hydrodynamic performance of each airfoil under various movement conditions.By analyzing the unsteady behavior of two-dimensional airfoils,we can understand the flow pattern,the generation,development and interaction of eddy currents and the influence on lift and drag in different movement processes.These as the basis for the work of the overall thesis identification.Secondly,the CFD numerical simulation of three-dimensional hydrofoil with wing-tip effect is carried out to study the influence of wing-tip on hydrofoil’s overall performance when pitch and heave motion of three-dimensional hydrofoil are done.The effects of different cross-section position.At the same time,the structure of the common three-dimensional hydrofoil is improved,and the hydrofoil structure with different wavy front forms is designed.Finally,hydrodynamic model experiments of three-dimensional hydrofoils with different leading edge structures are carried out in this thesis.The hydrodynamic performance of hydrofoils at different oscillation frequencies is studied,and the influence of different wavy leading edge structures on hydrofoil performance is analyzed.Wave front edge hydrofoils and common leading edge hydrofoils were simulated by CFD.The flow field was analyzed to investigate the disturbance mechanism of the wavy leading edge structure on hydrofoil boundary flow.