The Study Of The Deep-ocean Cylindrical Hydrophone

With the development of deep-sea water in recent years,deep-sea hydrophone development is imperative.The high hydro static pressure of the deep sea environment is destructive to hydrophones,so the traditional hydrophone cannot be carried out in the deep sea environment.In this paper,the structure of the hydrophone is analyzed and improved to solve the problem of deep sea work.In this paper,two different structures of the hydrophone were accumulated and simulated.In order to be able to take advantage of simplest manufacturing structure flow and simplest design,this paper chooses the air-backed round tube,which is simple and reliable in structure.First according to the elastic formula,the pressure formula of the piezoelectric ceramic tube under different depths is calculated,thereby it can derive the ratio of the inner and outer radii.Then,this paper use the vertical tube of the directionless and reciprocity method with ANSYS simulation to find the best height.At last,the finite element was built to plot the free-filed voltage receiving sensitivity curve.In this case the receiving sensitivity is-190 dB,the operating frequency band up to 10 kHz,the pressure value is 20 MPa.In order to better simulate the deep ocean environment,this paper derived the acceleration sensitivity of hydro hone and the program to weak its impact.The second structure is an overflow tubular hydrophone.Although the receiving sensitivity of the hydrophone of this construction is not very high,the liquid cavity can overcome the problem caused by the larger hydro static pressure.First,the theory of receiving sensitivity is deduced and corresponding formula is given.Then,the paper use ANSYS to analyze the different influencing factors,and the applicability of the model size is obtained and verified.The bandwidth of the overflow hydrophone is 6-24 kHz and the receiving sensitivity is-192 dB.Two types of air-backed and overflow hydrophone are fabricated and tested.Then this paper test the conductivity of the two hydrophones and the receiving sensitivity.The results show that the actual situation and theory are different,but the overall trend is consistent.Finally,make a 20 MPa pressure test.The results show that the performance of the hydrophones is excellent.