浅水中海洋核动力平台低频响应分析

Analysis on low frequency response of marine nuclear power platform in shallow water

与采用理论公式生成的波浪谱不同,实际浅水中的波浪谱密度在0~0.2 rad/s频率范围内会出现明显的低频能量成分,这会对海洋核动力平台的低频响应产生极大的影响。因此,基于数值模拟和水池试验2种方法得到的波浪谱,采用频域数值计算,分析平台在浅水中2种不同波浪谱下的纵荡、垂荡和纵摇低频响应。结果表明,与数值模拟波浪谱相比,在水池试验得到的实际浅水波浪谱中,平台的纵荡1阶低频运动响应和2阶低频波浪慢漂力,以及垂荡1阶低频波浪力和1阶低频运动响应都存在明显的增大,这说明在进行平台浅水水动力预报时需要重点考虑波浪谱中低频能量成分对平台低频响应的影响。本文可为其他同类型船体在浅水中的低频响应预报提供参考。

Unlike wave spectrums derived from the theoretical formula,the wave spectrums in real shallow water contain obvious low frequency energy part in frequency range of 0~0.2 rad/s,which would play a great influence on the LF response of marine nuclear power platform.Thus,based on the wave spectrums get from numerical simulation and basin test two methods,surge,heave and pitch LF responses in two different wave spectrums are analyzed adopting numerical calculation in frequency domain.Results shows that compared with the wave spectrums from numerical simulation,first order LF motion response and second order LF wave drift force in surge direction,first order LF wave force and first order LF motion response in heave direction all increase obviously in the real wave spectrums from basin tank,which means that it should pay more attention to the effect of LF energy part on the low frequency response of platform in the process of hydrodynamic prediction in shallow water.This paper can provide a helpful reference for the same type ships when proceeding the LF response prediction in shallow water.