摘要
采用水槽试验研究了水平杆件结构物水动力系数与波浪要素的基本关系.设计了垂直杠杆结构,用于提取波浪条件下杆件的水平受力过程线,有效地避免了波浪垂直运动对杆件水平力的影响.通过联立Morison方程,得到波浪作用过程中拖曳力系数Cd、惯性力系数Cm随时间的变化过程线,并首次采用傅里叶分析方法提取Cm变化的频域分布,利用三角函数进行拟合,分析拟合系数与波浪要素之间的关系.研究表明:在本试验波浪条件下,Cd呈现U形变化,但计算时仍可取为常数,不会产生大的误差;Cm由对应波浪的一倍和二倍频率的周期函数叠加而成,一倍频系数与波浪周期参数KT相关性较好,二倍频系数则与波高参数KH相关性较好,拟合所得的初始相角较为离散,取均值处理.为便于实际应用,给出了水动力系数与波浪要素关系的拟合公式,其与试验结果吻合较好.
The basic relationship between the hydro-coefficients of horizontal bar structures and wave parameters is studied using experimental tests in the tank. An upright lever structure is designed andused to extract the horizontal force curves from the total wave actions. It is considered as an effective way to avoid the interactions from the vertical wave motion. The variation curves of the drag coefficient C and the inert ial coefficient Cm are obtained by solving the Morison equations in timeseries. Furthermore , the distribut ion of the Cm in frequency domain is extracted using Fourier ＇s analysis method and through fitting by trigonometric function , and its relationship with waveparameters is discussed. The research results show that the Cd presents a U-shape variation with in thewave period. However,it can still be regarded as a constant in the wave force calculation w ith out causing major errors. The Cm is composed of two parts,the single-frequency part and the double-frequency part. The single-frequency part shows good relationship with the wave period parameter Kt , and the double-frequency part has good relationship w ith the wave height parameter K H. Theoriginal phase angle is rather discrete,and the average value is used. The empirical formulas of the relationship of hydro-coefficient and wave parameter are proposed for practical with the experimental results.
出处
《大连理工大学学报》
EI
CAS
CSCD
北大核心
2017年第2期164-169,共6页
Journal of Dalian University of Technology
基金
国家自然科学基金资助项目(51239002)
国家海洋局公益性行业科研专项经费资助项目(201505025-2)
舟山市海洋专项(2015C41001)
关键词
水平杆件结构物
水动力系数
波浪要素
波浪力
拟合公式
horizontal bar s truc ture
hydro-coefficients
wave parameters
wave fo rce
empiricalformulas
