通过理论推导和数值模拟验证,对基于变折射率光学透镜原理设计特殊变密度流体域来控导水面波的机理开展了研究。 研究结果表明,依据让光线转向的Eaton透镜设计的变密度流体域可以让平行入射的水面波转向传播,使得下游区域的波浪强度明显减弱,从而减轻涉水工程受到波浪影响;而依据让光线聚焦的Luneburg透镜设计的变密度流体域可以让平行入射的水面波聚焦于一点,使得该点波浪强度显著增强,进而利于波浪能的收集利用。进一步分析表明,根据具体工程需求和现场条件,设计和布置不同大小和功能的变密度流体区域,从而实现对水面波的调控是具可行性的。该理论和方法可为水利和海洋工程中制定波浪的防范和利用措施提供新的思路。
The mechanism of controlling water wave by designing special variable-density fluid is studied through theoretical analysis and numerical simulation based on the principle of gradient refractive index optical lens.The impact of water waves on water-related projects can be alleviated by designing variable-density fluid lens to make parallel incident water waves turn back and propagate backwards according to the principle of the Eaton lens which could deflect ray trajectories,hence reducing wave intensity in downstream area.On the other hand,water wave energy can be better collected and exploited by designing variable-density fluid lens to make parallel incident water wave focus to a point and enhance wave intensity in light of the Luneburg lens which can focalize ray trajectories.Our study proves that it is feasible to regulate and control surface water waves by designing and arranging variable-density fluid regions of different sizes and functions according to specific application requirements and project conditions.The theory and technique in this paper provides a new idea for controlling and utilizing waves in water conservancy and ocean engineering.
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