Study of the Attenuation of Point Source Sound Propagating through a Circular Bubble Curtain

• Main Authors: Han-TaoCheng, 鄭翰濤
• Other Authors: Ching-Jer Huang
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/67142047068200428354

碩士 === 國立成功大學 === 水利及海洋工程學系碩士在職專班 === 104 === The diversity and amount of marine activities in oceans has increased over the past few decades, and these activities generate intense sound into the marine environment, which has been identified as a potential threat to marine mammals. Due to global energy shortages, many countries have developed methods to make use of renewable energy, and while the development of offshore wind energy is likely to play a major role in this, the pile driving needed when laying the foundations of wind turbines in water produces high sound levels in the underwater environment. In order to mitigate underwater noise, piles being driven into a seabed are usually surrounded by curtains of freely rising air bubbles. Commander and Prosperetti (1989) developed an effective theory of one-dimensional plane wave propagation through bubbly liquid. To model the real underwater sound source surrounded by air bubble curtains, in this work we develop a three-dimensional mathematical model. We assume that the sound is a spherical monochromatic wave from a point source, which propagates through a circular air bubble curtain. A comparison of the results of the theory and experimental data show that the values are overall in agreement.