波浪与双层水平板防波堤相互作用试验研究

Experimental study on waves interacting with horizontal twin-plate breakwater

采用物理模型试验的方法,研究波浪与双层水平板防波堤相互作用。研究结果表明:波浪与双层水平板防波堤作用后,双层水平板起到了消波(反射和损耗部分波浪能量)和改变波频的双重作用。潜式堤和出水堤堤后的波面含有2阶及以上谐波成分,特别是当相对板宽小于0.5时,高阶谐波成分占有能量比例较大,一定条件下可达到1阶谐波占有能量比例相当的程度。因此采用谐波能量叠加法定义的透射系数更具合理性。透射系数受诸多参数的耦合影响,并非双层水平板越宽,对单色波浪的消浪效果越好,在0~1倍相对板宽范围内,透射系数随相对板宽的变化呈波动形式;在相对潜深d/D=-0.25^+0.17试验范围内,相对潜深对透射系数的影响并不十分显著。

The interaction between waves and horizontal twin-plate breakwater was studied by the method of physical model test. The results show that when the wave interacts with the horizontal twin-plate breakwater, the breakwater can absorb wave energy （reflect and dissipate part of the wave energy） and change wave frequency. Wave surfaces behind the submerged and emerged breakwaters contain the second and high order harmonics. Especially when the relative plate width is less than 0.5, the high order harmonics occupies a high proportion of wave energy, which can reach to the same proportion of wave energy as the first order harmonics under certain conditions. Therefore, it is more reasonable to adopt the transmission coefficient defined by the harmonic energy superposition method. The transmission coefficient of the horizontal twin-plate breakwater is influenced by many coupling parameters. For the monochromatic wave, the breakwater may not work better with wider twin plates. The trans- mission coefficient shows a fluctuated type with relative plate width ranging from 0 to 1. However, when the relative depth d / D is in the test range from -0.25 to 0.17, the influence of the relative depth on the transmission coefficient is not significant.