Hydrodynamic Performance Analysis And Dynamic Modeling For AUV

In recent years,with the development of Marine science and technology,Autonomous underwater vehicle(AUV)has played an important role in the field of Marine science,military and commercial sector.AUV is a highly nonlinear and parameter time-varying system,thus,establishing an accurate model of AUV is very important for its control,prediction and simulation.The model of AUV established is accurate depends on its hydrodynamic parameters,so the hydrodynamic parameters become more and more essential.Firstly,this dissertation takes an autonomous underwater vehicle as the research object,establishes the mathematical model of six-freedom motion of underwater vehicle based on the space six-degree-of-freedom motion equation of Newton-Euler equation.Then the dissertation analyzes the relationship among the force,torque and hydrodynamic coefficient of underwater vehicle.Secondly,the CFD method is used to divide the underwater vehicle into meshes,then a numerical calculation model is established to carry out direct numerical calculation.The calculated data was compared with sink drag test data to verify the feasibility of the numerical calculation.At the same time,the influence of the GPS antenna model on the paddle surface of the wake field was analyzed,and a better GPS antenna model type was obtained.Furthermore,the numerical calculation of the tail and the body were carried out respectively.Then,the hydrodynamic coefficients corresponding to the direct cruising and inclined voyage were obtained.Then,the six-degree-of-freedom motion of the underwater vehicle is numerically calculated using the dynamic mesh technology in Fluent to obtain the corresponding hydrodynamic coefficients.According to the hydrodynamic coefficients obtained by numerical calculation,further coupling calculations are made to obtain other hydrodynamic coefficients which are difficult to directly obtain.Finally,the stability of the underwater vehicle is analyzed according to the hydrodynamic coefficients.At the same time,the manipulability and spatial mobility of the underwater vehicle are simulated through Matlab.