It is important to achieve a better understanding of the wave energy variations occurring as a steep wave evolves towards breaking. Laboratory experiments of focused waves are performed to investigate the kinematics of primary breaking waves. When a primary wave evolves towards breaking, the increase in the maximum kinetic energy is stronger than the increase in the maximum potential energy. Furthermore, the accuracy of the average energy of the wave train analyzed by the wave spectrum is discussed. At measuring locations far from the breaking onset point, the average energy of the wave train analyzed by the wave spectrum is slightly larger (0.6–2.5%) than the average energy calculated by the measured free-surface elevation and fluid velocities. In contrast, at measuring locations close to the breaking point, the nonlinearity of the wave train is strong and the average energy analyzed by the wave spectrum underestimates the measured wave energy. The error ranges of the total energy loss rate of deep-water wave breaking calculated by wave spectrum analysis are 1.5–3.79% and ±1.9% for measuring locations close to and far from the breaking point, respectively. Although the absolute value of the error is not prominent, the error range is not negligible relative to the energy loss rate of a single spilling wave. Finally, a wave index ϵ ∗ (f_s/f_p) is proposed to reveal the characteristics of the wave energy variations during the incipient breaking stage under different wave conditions.

中文翻译：

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深水中聚焦溢流的速度和能量的实验比较

重要的是要更好地理解随着陡波向破裂演变而产生的波能变化。进行了聚焦波的实验室实验，以研究初级破碎波的运动学。当一次波向破裂方向发展时，最大动能的增加要强于最大势能的增加。此外，还讨论了通过波谱分析的波列平均能量的准确性。在远离断裂起点的测量位置，通过波谱分析的波列的平均能量比通过测得的自由表面高程和流体速度计算出的平均能量稍大（0.6-2.5％）。相反，在接近断裂点的位置进行测量 波列的非线性很强，通过波谱分析得出的平均能量会低估测得的波能。通过波谱分析计算出的深水波折断的总能量损失率的误差范围分别为在接近和远离折断点的位置进行测量的1.5–3.79％和±1.9％。尽管误差的绝对值不显着，但相对于单个溢波的能量损失率，误差范围不可忽略。最后，波指数ϵ ∗（尽管误差的绝对值不显着，但相对于单个溢波的能量损失率，误差范围不可忽略。最后，波指数ϵ ∗（尽管误差的绝对值不显着，但相对于单个溢波的能量损失率，误差范围不可忽略。最后，波指数ϵ ∗（f _s / f _p）的提出是为了揭示在不同波浪条件下初期断裂阶段波浪能的变化特征。