双色波作用下港池长周期波浪模拟研究

Long-period wave numerical modeling in harbour basin under bichromatic waves

防波堤对长周期波浪的掩护较差,长周期波浪容易直接侵袭港内,恶化港内作业条件。依托物理模型试验结果,基于BW数值模型研究双色波作用下港池长周期波浪产生机制。对BW数值模型进行验证,模型与试验结果吻合良好。在频率分别为f_(1)和f_(2)的双色波作用下,波浪间发生非线性作用产生Δf、2f_(1)-f_(2)、2f_(2)-f_(1)、2f_(1)、f_(1)+f_(2)、2f_(2)等频率的波浪,当产生的长周期波浪Δf与港口自振频率趋于一致时,长周期波浪波高被港池捕捉发生共振而放大。随着双色波入射波高、调谐率的增加,波浪之间的非线性作用增强,长周期波高显著增大。

The breakwater has poor protection against long-period waves,which can easily invade the harbor directly and worsen the operating conditions in the harbor.This paper relies on the physical model test results and the BW numerical model to study the generation mechanism of long-period waves in the harbor pool under the action of two-color waves.The BW numerical model is verified,and the model agrees well with the test results.Under the action of two-color waves with frequencies f_(1) and f_(2) respectively,nonlinear interactions occur between waves to produce waves with frequencies such as Δf,2f_(1)-f_(2),2f_(2)-f_(1),2f_(1),f_(1)+f_(2),and 2f_(2).When the wave frequency Δf equals to the harbour natural frequency,the wave height of such wave frequency will amplify.The nonlinear interaction of waves is positively associated with the increment of wave height and tenability,which results in the increase of long-period wave height.