风雨条件下的水下噪声谱级预测

Prediction of underwater noise spectrum levels under different conditions of rain and wind

海洋表面的风、雨所产生的噪声是水下噪声场的重要组成部分。降水时雨致噪声可在比较宽的频带内决定噪声场的性质。在1~50kHz频段上,对已有的相关研究结果分析、综合,建立了一定风雨条件下的水下噪声谱级的经验预测算法。采用按频率线性分配大、小雨滴对噪声能量谱密度贡献的方法,在9~14kHz频段上对经验算法进行了修正。该修正经验算法不仅克服了经验算法在10kHz处经验预测值的跃变问题,而且通过两种算法预测值与某海域的实际观测数据的对比,表明修正经验算法比经验算法可以在更宽的频带内更加有效地预测一定风雨条件下的水下噪声谱级。

Sound generated by wind and rain from the ocean surface is confirmed to be an important part of ocean noise background.The rain falling down to a large area of water surface produces dominating underwater sound over a broad range of frequencies.The empirical algorithm is constructed to calculate noise spectrum levels under different conditions of rain and wind by analyzing,synthesizing the results of earlier research.In the band from 9 kHz to 14 kHz,the contribution of noise energy produced by the small and large raindrops is commixed by linear proportion to modify the empirical algorithm.The modified empirical algorithm overcomes the discontinuity at the frequency of 10kHz predicted by the empirical algorithm,and is proved to be better by comparison with the observed data in the ocean.