The Research Of Vector Hydrophone Low Frequency Calibration Device

This paper, for the difficulties of vector hydrophones low frequency calibration in thefree field, uses standing wave field theory developed a set of vector hydrophone lowfrequency calibration device.The paper has analyzed the sound field on vector hydrophone standing wave field ofcalibration principle and round, the open end of the filling liquid pipe. According to the actualneed of calibration frequency, it designs two requirements of the measure calibration tube,completes calculation and analysis of the tube acoustic field distribution, especially thepressure and vibration acceleration in different frequencies the relationship of change withdepth in the pipe sound, and gives the best depth of the vector hydrophone calibration. At thesame time, it uses the ANSYS simulation software to analysis the sound field, the analysisresults is better match to the measured results. It has designed the piezoelectric transducersarray for the small calibration pipe and electric transducer for the big calibration pipe to makea plane wave sound field. This paper also calculates the mechanical model vector hydrophoneand the influence of measurement media, the results show that there is a little different in thesensitivity of vector hydrophone in different medias, about0.5dB or so. The research ofcalibration device includes the design of the program-controlled drive vertical return, theselection of measuring instrument and the design of the measuring software.Finally, the whole system is done uncertainty analysis.6times repeatability tests ofvector hydrophone in each two calibration systems have been done, and get enough date toanalysis. To analysis the systems, it uses two standard vector hydrophones to measure thesystems. Compared measurements, the system has the biggest different of measurementresults in250Hz, at0.8dB.The uncertainty of devices is verified.