Research And Design Of Small Surface Drifting Buoy Based On Wave Resistance

Ocean data buoy is an important observation device placed in the ocean to obtain marine information.As a type of small ocean observation buoy,the surface drifting buoy is small and light,it can be used monitoring the ocean currents,pollutants and ocean oil spills,marine meteorology,marine rescue,physical and chemistry characteristics of seawater and deep sea profiles,etc,which is of great significance to marine environmental investigation and protection of the marine environment;buoys usually need to be equipped with a variety of measuring instruments and communication equipment,in order to ensure the stable and continuous operation of the internal systems and prolong the working life of the buoy,the motion state and amplitude of the buoy under wave are particularly important;therefore,improving the wave resistance of the buoy under wave by optimizing the shape and structural parameters of the buoy is of great significance to surface drifting buoys.According to the research status and development trend of surface drifting buoys,based on the considerations of the working environment of surface drifting buoys,the equipment and the stability of the buoy movement,the shape and sture parameters of the small drifting buoys were studied and designed.The optimization provides reference for the theoretical design and technical application of surface drifting buoys.The main research work and innovation of this article are as follows:(1)First,the wave transmission performance of the numerical wave tank is in depth studied.A detailed comparison study of the wave transmission performance of the traditional pure viscous numerical wave tank trough with damping wave elimination and the new type numerical tank based on Euler nesting combined with the potential and viscous flow used in this paper,strictly verify the convergence of the setting parameters such as the specific grid and calculation time step of the numerical wave tank.Finally,a new type of numerical wave tank establishment and parameter setting method based on potential and viscous flow is summarized,which provides a more superior performance method for the establishment of numerical wave tank,and at the same time lays the foundation for the next study of the buoy hydrodynamic characteristics and wave resistance.(2)Then,the theoretical analysis of the buoy movement under the action of still water and waves was carried out,the method of obtaining the natural frequency of the buoy and the method of increasing the natural frequency of the buoy to improve the performance are determined,carry out multiple sets of motion simulations to prove the correct conclusion.Than,combined with the common small buoy shape and structure,design the spherical,cylindrical and disc-shaped buoys and simulate the free decay motion of heave and pitch in the numerical water tank,and obtain the natural frequencies of the heave and pitch of the buoy,compare the changes of each group of buoy parameters and their natural frequencies to determine the influence of each parameter on the natural frequencies of different buoy shapes,and provide a reference and data support for the above three shapes of buoy design and subsequent buoy selection.(3)Combined with the shape and parameters of the existing small surface drifting buoy and the previous research results,the surface drifting buoy design scheme of the gourd shape body was finally determined,the shape parameters and fluid results were compared with the traditional buoy shape to determine the advantages of the gourd shape.Then,according to the working environment of the buoy,the wave motion of the gourd shape buoy was responded under different sea conditions.The effects of the sea state level,the distance between the center of gravity and the buoy center,the moment of inertia and other parameters on the wave performance of the gourd shape buoy were simulated.The results prove the feasibility of the gourd shape as the main body of the small surface drifting buoy.The simulation date results provide a reference for the design of the gourd shape surface drifting buoy.