海上风电场运营期水下噪声测量及特性初步分析

摘要

Underwater noise from the operation of offshore wind farms has impacted the marine environment. Underwater noise was recorded from one 3.0 MW and one 5.0 MW wind turbine in Shanghai during a normal operation phase in this paper.Finally,a normal mode propagation model was designed to predict the noise distribution of wind turbines.The results of the data processing show that noise during operation is of a much lower intensity and generally dominated by a series of pure tones below 800 Hz.The dominating frequencies become obvious at high wind speed.The sound intensity increases with the wind speed but has no significant difference with the power of the wind turbines.In addition,the frequency content of the noise seems to change with the power of the wind turbines,the wind speed and the foundation type.The zones of the noise effects on the marine environment are small during the operation of the wind farms.The results of this paper can provide technical information for environmental impact assessment of offshore wind farms and have great value in engineering applications.%海上风电场运营期间产生的水下噪声影响了海洋生态环境。针对国内对风机水下噪声定量研究的缺乏，测量分析了海上风电场运营期单机容量3．0 MW 和5．0 MW 风机产生的水下噪声，并利用简正波模型仿真噪声分布。数据处理结果表明，风机产生的水下噪声强度较低，集中分布在800 Hz 以下的低频段，噪声谱具有主频特性，高风速下主频更加明显；噪声强度随风速的增加而增大，而与风机功率差异不明显；噪声谱主频分布与风机功率、风速、桩基结构等有关。总体看，单个风机运营期间产生的水下噪声对海洋生态环境影响区域小。现场测量数据及结果可为海上风电工程环境影响评价提供技术参考，具有较大的工程应用价值。