为明确水下排气噪声发生的空间位置,掌握流动形态对排气噪声的影响特征,在水池中通过水下摄像和噪声监测方法研究了瞬态水下排气过程。结果表明:40 mm管口水下稳定排气产生的气泡直径约3~21 mm,气泡群上浮平均速度为0.31 m/s;水下排气噪声主要发生在排气管口附近,在气泡形成过程中产生,单极子辐射占主导地位,是水下排气的主要噪声源;气泡上浮时的噪声总级远低于管口气泡形成噪声,与背景噪声接近,是水下排气中可以忽略的噪声源,其频谱特征中主要是气泡固有频率,峰值频率约800 Hz;气泡在水面破碎时产生的噪声比排气出口噪声略低,是水下排气的次要噪声源,偶极子噪声占主导地位。
In order to reveal the location of sound emit by underwater air flow and influence of flow conditions on sound characteristics,the transient process of underwater air flow experiment is researched in a deep pool with the help of images and hydrophones. The results show that the diameter of bubbles generated by underwater air flow ranges from 3 mm to 21 mm,the mean velocity of bubble floating up is 0.31m/s. The sound emission is mostly induced by bubble formation near the nozzle, which shows the behavior of monopole noise. The sound induced by bubble floating up is much lower than that of bubble formation, which can be ignored because it is very close to the background, the spectral band is coincident with the bubble diameters, and the submit of the noise is 800 Hz. The sound induced by bubble breakup at the water surface is lower than that of bubble formation, which shows the behavior of dipole noise.
2023,45(5): 20-25 收稿日期:2022-05-05
DOI:10.3404/j.issn.1672-7649.2023.05.004
分类号:O357.5
基金项目:国家自然科学基金资助项目(91634110)
作者简介:邓鹏(1987-),男,博士,主要从事船舶系统工程研究