Effect Of Finite Baffle On Direction-finding Of Vector Hydrophone

Today, with the high speed development of technology, vector hydrophone has been widely applied to almost every area of underwater acoustics. But in more applications, the vector hydrophone need to be tied on ships, dam and some other structures. The scattering of these structures must has the influence on vector hydrophone's direction finding. In this thesis, the scattering-pressure and the scattering-velocity of the point which the vector hydrophone is on in the near sound field of the baffles has been calculated and the influence on the direction estimate of vector hydrophone which is near the baffles has also been analysised.In this thesis, the basic theory of vector hydrophone has been introduced first. For example, the kinds of vector hydrophone, the directivity of vector hydrophone, the methods of direction-finding. Meanwhile, I've also been researched some influencing factors of the direction estimate when there is no baffle near the vector hydrophone.Then, the influences of the plate baffle and the sphere baffle on the vector hydrophone have been researched detailed. With the theory research of the acoustic filed near these two baffles, the pressure and the velocity of one point under the influence of baffles has been known. Meanwhile, with the method of FEM(Finite Element Method) +BEM(Boundary Element Method), the acoustic scatting near the baffle has been researched. In this method, I use two software named ANSYS and SYSNOISE to calculate the acoustic scatting of the baffles. With the result of these two software, the angle distributing function curve of the pressure and the velocity has been gained, then the result of direction-finding of the vector hydrophone which is on the same point has also been researched.At the end of this thesis, with the data of the lab in the anechoic tank, the theory of the angle distributing function curves of the pressure and the velocity at the point where the vector hydrophone is and the results of direction-finding of the vector hydrophone when there is a baffle near it have been confirmed.