Water particle velocities measured under ocean waves
Water particle velocities measured under ocean waves
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海浪下测量的水粒子速度
DOI：
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发表时间：
1974
期刊：
影响因子：
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通讯作者：
R. F. Krapohl
中科院分区：
文献类型：
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作者：
E. Thornton;R. F. Krapohl
用穿透波尺和电磁流量计在19 m水深的6个高程上同时测量了波浪和两个正交的水质点速度。在实验期间，普遍存在中等涌浪和低风条件。实测的波浪诱导速度比用线性波理论计算的大2-4%。波高和波诱导速度在显着的能量密度范围内的相干性计算为0.85以上，表明运动几乎完全是波诱导的。在较高的频率下，很明显，运动主要是湍流。相谱计算测得的波高和轨道速度相比，非常好的线性理论。测量的频率分布进行了比较，高斯和Gram-Charlier分布，通过使用卡方拟合优度检验。定性地，Gram-Charlier分布给出了更好的拟合数据，表明弱非线性系统。
Simultaneous measurements of waves and two orthogonal water particle velocities were made at six elevations in 19 m of water by using a penetrating wave staff and an electromagnetic flowmeter. Moderate swell and low-wind conditions prevailed during the experiment. The measured wave-induced velocities were 2–4% greater than those calculated by using linear wave theory. Coherence of the wave height and wave-induced velocities in the significant energy-density range was computed to be over 0.85, indicating that the motion was almost totally wave induced. At higher frequencies it was apparent that the motion was primarily turbulence. Phase spectra computed for the measured wave heights and orbital velocities compared very well with linear theory. Measured frequency distributions were compared with both Gaussian and Gram-Charlier distributions by using the chi-squared goodness-of-fit test. Qualitatively, the Gram-Charlier distribution gave the better fit to the data suggesting a weakly nonlinear system.