静水压下水声吸声材料研究现状

With the rapid technological advancements, sonar technology has made remarkable progress in recent years. This advancement not only facilitates the advancement of sonar technology, but also imposes stricter requirements on the stealth performance of underwater equipment, such as submarines. Consequently, hydroacoustic absorbing materials (HAMs) have emerged as indispensable tools for achieving acoustic stealth in such equipment. Extensive research has been conducted on HAMs in recent years. However, due to the faster propagation speed and longer wavelength of underwater sound waves compared to airborne sound, effective sound absorption becomes increasingly challenging. Additionally, considering the higher density of water, sound absorbing materials must be able to withstand high-level pressure, particularly in deep-water environments. These factors pose significant challenges in designing efficient HAMs. Previous studies have demonstrated that hydrostatic pressure has a significant impact on the acoustic properties of HAMs. Under hydrostatic pressure, the matrix parameters of HAMs undergo changes, and the internal acoustic structure is squeezed and deformed. This specifically leads to reduced sound absorption in low frequencies. Currently, the design of low-frequency and wideband HAMs under high hydrostatic pressure remains a challenging task in this field. Therefore, further investigation is needed to analyze and optimize sound absorption. This review provides an extensive overview of the current research status on analysis methods for acoustic absorption in HAMs under hydrostatic pressure. The focus is primarily on theoretical and experimental analysis methods. Additionally, this review summarizes the sound absorption mechanisms of HAMs and examines how hydrostatic pressure impacts these mechanisms. Specifically, under hydrostatic pressure, the damping dissipation effects caused by internal friction and relaxation processes within the matrix material of HAMs are diminished. Furthermore, compression deformation weakens resonance effects in acoustic structures, such as cavities or local resonances, ultimately leading to a decrease in the sound absorption performance of HAMs. This review further summarizes the design considerations for existing HAMs. Regarding the matrix material, enhanced pressure resistance and sound absorption performance can be achieved through a combination of diverse materials and specialized structures. In terms of acoustic structure, superior pressure resistance and sound absorption capabilities can be achieved by incorporating reinforced structures that exhibit increased resistance to hydrostatic pressure or by employing innovative metamaterial designs. Finally, the review presents a forward-looking perspective on the research trends in HAMs under hydrostatic pressure. Currently, a significant challenge remains in balancing hydrostatic pressure resistance and low-frequency broadband sound absorption. There is a pressing need for more meticulous designs of acoustic models suitable for high-pressure conditions exceeding 4.5 MPa. These unresolved questions represent crucial areas for future investigations. It is anticipated that this review will provide novel insights into the design of materials with sound absorption capabilities under hydrostatic pressure, paving the way for future advancements in this field.