上海东海大桥海上风电场水下噪声特性分析

随着对清洁能源利用的逐步重视,我国海上风电产业发展迅猛。人为活动所产生的水下噪声是近几年备受关注的环境问题,而我国对海上风电场水下噪声的相关科学研究却几乎一片空白,因此实验对上海东海大桥海上风电场运行期噪声进行了实地调查采样,并进行数据分析。分别研究了不同单机容量风电机的噪声特性,并对风电场内单个风机分不同深度进行了噪声特性研究,还对不同噪音测量方法进行了对比。结果表明:风电机噪音具有低频及低能级水平的特点,主要频率在400 Hz以内,声压级在81~101 d B之间。海水流速一定时,不同深度风电机水下噪声频谱特性基本一致;当海水流速增大,会导致频谱部分主频峰值的丢失或偏移。噪声记录使用的抛锚定点测量法空间自由度高,但测量时间较被动;漂流法测量路线单一,但测量时间自由度较高。

Characteristics of underwater noise from Shanghai Donghai Bridge offshore wind farm

As the use of clean energy increasingly gains attention, China''s offshore wind power industry has been developing rapidly in recent years. However, the underwater noise from the wind power station has not been studied in our country while the noise from human activities as an environmental issue has attracted much concern around the world in the last few years. In this study, we collected the operational noise data from the offshore wind turbines in the vicinity of the Shanghai Donghai Bridge and studied the characteristics of different wind turbines. We compared the noise data from different depths of water, as well as compared the data collected by using different measurement methods. The results show that the noise data from each single wind turbine shares the characteristics of low frequency and low sound pressure level:the main frequency range is within 400 Hz and the sound pressure level is between 81 dB and 101 dB. The characteristics of underwater noise from different depths are basically the same when seawater flowing speed keeps constant, but when the speed increased, some of the main frequency lost or shifted. The fixed-point method we used can measure any location we set, but the measurement time is limited. Drift method can measure at any time but the measurement line is limited.