NUMERICAL SIMULATION STUDY OF UNDERWATER ACOUSTIC ATTENUATION EFFECTS BY BUBBLE CURTAINS

The use of bubble curtains for underwater acoustic shielding is a crucial research area in ocean and environmental engineering. Recent advancements have focused on optimizing bubble curtain technology through innovative approaches, attracting considerable attention from both academia and industry. In this study, the Multi-Component Flow Code (MFC) is employed alongside an ensemble-averaged multiphase flow model, considering bubble-fluid interactions, to simulate the dynamics of bubble curtains under various parameter configurations and evaluate their effectiveness in underwater acoustic shielding. The primary parameters investigated include bubble size distribution, volume fraction, curtain thickness, and ambient pressure, all of which significantly influence the shielding performance. The simulation results indicate that acoustic energy attenuation is positively correlated with the bubble volume fraction, with higher volume fractions leading to greater attenuation. The bubble curtain demonstrates superior shielding effectiveness in acoustic fields characterized by low amplitude and high frequency. Within certain parameter thresholds, increasing the thickness of the bubble curtain can effectively enhance its sound attenuation capabilities. Additionally, there is an optimal initial bubble radius and standard deviation that maximize the peak attenuation of sound waves. However, in polydisperse bubble distributions, the reduction in sound attenuation is limited. As the ambient pressure increases, the attenuation effect gradually diminishes, with the attenuation rate approaching a minimum and stabilizing when the water depth exceeds a certain threshold. Furthermore, the study explores the peak sound attenuation effect for various acoustic field conditions, including different amplitudes and frequencies, providing a comprehensive understanding of how bubble curtain configurations can be optimized for maximum performance. The findings suggest that adjusting the distribution and volume fraction of bubbles, as well as the curtain's thickness, can significantly improve sound attenuation. This research offers valuable theoretical insights and practical guidance for the design and optimization of bubble curtain technologies, facilitating more effective underwater noise control solutions in various engineering applications.