Design And Development Of Hydrophone Based On Electrochemical Transducers

With the further development of marine science,sound pressure hydrophone,as the receiving and converting unit of sonar,not only plays an important role in resource exploration,underwater communication and target orientation,but also occupies an indispensable position in the military field.For application in the deep sea,the low frequency performance of sound pressure hydrophone is increasingly required,which has become a research focus in recent years.However,the response sensitivity of traditional piezoelectric ceramic sound pressure hydrophone to weak low-frequency signals is small and the finished product is vulnerable to damage.And the production process of fiber-optic sound pressure hydrophone is complex and expensive.Therefore,an electrochemical sound pressure hydrophone is designed in this paper.Compared with current sound pressure hydrophones,it has the advantages of high signal reduction,high sensitivity,good low-frequency performance and simple production process.In addition,because electrochemical sound pressure hydrophone uses electrolyte as the vibration unit,it also has the characteristics of good plasticity and high impedance matching with the liquid environment.So it is very suitable to detect underwater lowfrequency sound signal.In this paper,the mathematical model of electrochemical sound pressure hydrophone is established and the multi-physical simulation model is established for simulating and analyzing.Of course,an electrochemical sound pressure hydrophone prototype is designed and tested.First of all,we combine the electrochemical seismometer and the traditional sound pressure hydrophone and proposes an electrochemical sound hydrophone.The design concept of electrochemical sound hydrophone is described in detail from mechanical structure and working principle.Its mathematical model is established and the expression of transfer function is calculated,which provide a theoretical basis for follow-up work.Secondly,the electrochemical hydrophone simulation model is established in the Comsol Multiphysics.Its working process,output characteristics and scope of application are simulated and analyzed in different physical fields.Some structural parameters of the hydrophone are optimized by analyzing simulation results.And the hydrophone output current sensitivity curve is drawn to help the circuit design.An electrochemical hydrophone analysis app is made by using exclusive function of Comsol,which makes the simulation model easier to reuse and improve work efficiency.Then,according to simulation results and requirements of the hydrophone,the analog circuit is designed.The output current of electrochemical transducer is amplified and filtered,and the loop feedback is introduced to adjust the amplitude and frequency characteristics of the hydrophone for wider application range.Finally,the electrochemical hydrophone prototype is manufactured with appropriate materials.According to the current test method of sound pressure hydrophone,the experimental scheme is designed,and appropriate instruments are selected to build experimental environment.Performance of electrochemical sound hydrophone is tested from different aspects.The experimental result shows that the hydrophone prototype has a high sensitivity of-152 d B(± 1d B)and a flat sensitivity level curve of in the frequency band of 0.8Hz～10Hz.Within the range,the input-output linear correlation coefficient is higher than 0.99,and linearity of the hydrophone prototype is good.The background noise amplitude of the hydrophone is 4m V～8m V,which is far less than the marine environmental noise in the frequency band of 0.1Hz～10Hz.From experimental result,we can see that the hydrophone prototype achieves the design objectives and electrochemical sound pressure hydrophone has a certain application prospect for detecting low-frequency underwater sound signal.