燕尾坎挑流消能噪声的影响因素分析

通过燕尾坎挑流消能的水工模型试验,测量了某重力坝泄洪过程中产生的噪声强度,分析了测点位置、流量、闸门开启方式与噪声强度的关系。基于相似原理,把噪声强度结果换算到原型,从频率和等效声级两方面分析了水流噪声对库区居民和动物的影响。结果表明,水流噪声主频位于低频段,噪声强度最大值出现在32、40 Hz频率处。流量和闸门开启方式相同时,挑坎末端断面附近低频噪声强度最大,挑流水舌进入水垫塘区域的高频噪声强度最大。闸门开启方式不变,流量越大,各测点对应频率的噪声强度越大。流量不变,开启孔数越多,各测点的噪声强度越大。调整运行调度方式,可以在一定程度上降低噪声强度。该结果可为分析水利水电、防洪、景观工程水流噪声的特性和减缓水流噪声的不利影响提供技术支持。

Analysis of Influencing Factors of Ski-Jump Energy Dissipation Noise with Dovetail Camp

Through the hydraulic model test of the ski-jump energy dissipation of the dovetail camp, the noise intensity generated during the flood discharge process of a gravity dam was measured, and the relationship between the location of measurement points, flow rates, gate opening modes and noise intensity was analyzed. Based on the similarity theory, the experimental results of noise intensity were converted to the prototype, and the influences of water flow noise on the residents and animals in reservoir area were analyzed from two aspects of frequency and equivalent sound level. It was found that the main noise frequency of the flow fell within the low frequency band, while the maximum noise intensity appeared at the frequencies of 32 Hz and 40 Hz. With the same conditions of flow discharge and the sluice gate opening mode, the maximum low value of noise frequency appeared at the flip bucket, while the maximum high value of noise frequency appeared at the stilling pool. Using the same sluice gate opening mode, the noise intensity tended to increase with the flow discharge. Under a constant discharge, the more holes of sluice gate, the greater noise intensity. The present investigation highlights that the noise intensity can be reduced by adjusting the operation scheduling mode, which provides a technical support for analyzing the characteristics of flow noise in flood control project, water conservancy project and landscape engineering.