Deep water characteristics of electrodynamic transducers based on distributed-parameter equivalent circuit of acoustic cavity

Yongjie Sang; Yishuang Zhang; Shuai Wu

doi:10.1121/10.0034419

Deep water characteristics of electrodynamic transducers based on distributed-parameter equivalent circuit of acoustic cavity

J Acoust Soc Am. 2024 Nov 1;156(5):3384-3395. doi: 10.1121/10.0034419.

Authors

Yongjie Sang^{1

2

3}, Yishuang Zhang³, Shuai Wu³

Affiliations

¹ National Key Laboratory of Underwater Acoustic Technology, Harbin Engineering University, Harbin 150001, China.
² Key Laboratory of Marine Information Acquisition and Security (Harbin Engineering University), Ministry of Industry and Information Technology, Harbin 150001, China.
³ College of Underwater Acoustic Engineering, Harbin Engineering University, Harbin 150001, China.

PMID: 39555946
DOI: 10.1121/10.0034419

Abstract

The source level of the electrodynamic transducer with a passive pressure compensation airbag in ultra-low frequencies (bands below 100 Hz) decreases sharply with the increase in working depth. A theoretical model with a distributed-parameter equivalent circuit of the acoustic cavity was proposed to explore the mechanism of this phenomenon and find a way to improve the ultra-low frequency source level in deep water (over 200 m). The results indicate that the decrease in acoustic compliance of the cavity in deep water leads to an increase in resonant frequency, resulting in a decrease in source level in the ultra-low frequency band. The resonance frequency in deep water shows differences based on distributed and lumped parameter models. The resonance frequency test results of the prototype show that the theoretical results based on a distributed-parameter model proposed in this study are more consistent with the test values. The effects of the acoustic cavity's structural size, the acoustic parameters of the gas in the cavity, and the active pressure compensation method on the source level at different depths were analyzed. Results reveal that the acoustic performance in ultra-low frequency bands at large depths can be markedly improved using the active pressure compensation method.