2009-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/691028摘要：由於海洋活動隨著人類文明逐漸頻繁，海洋結構物之安全性也就逐漸重要。由於複雜之波浪外力造成結構物設計上的困難，而其中非線性波浪作用現象最為複雜。近年來學者致力於非線性波浪之理論研究不遺餘力，然而理論模式之正確性尚有改善之空間，追根究底歸因於人們對非線性重力波物理現象之瞭解不足，因此本研究將針對此一問題作深入探究。 本計劃為二年計劃，將在國立台灣大學工程科學及海洋工程學研究所之基礎流力實驗室進行，其主要設備包含可程式之活塞式造波機、長20m、寬0.3m、深0.6m之斷面水槽、National Instrument之AT-AO-6介面卡、Spectra-Physics之Stabilite 2017-04S雷射、Kodak MotionCorder Analyzer之Model SR-Ultra高速灰階數位相機。利用一4W之Argon Ion雷射及高速攝影機所建立之粒子影像流場量測技術，觀察量測不同波浪型態下之粒子運動軌跡對質量傳輸及表面波型之影響。 第一年度之執行重點在利用粒子軌跡之曝光影像量測技術對深水、中間及淺水波浪條件之粒子軌跡型態進行量測，並針對量得之軌跡與現有理論(Linear Wave Theorem；Stoke 2nd order waves; Cn waves)進行比對驗證，更進一步計算不同Ka值時其相對應之質量傳輸率為何。第二年則在探討非線性波-波交互作用下水粒子運動軌跡對波浪交互作用表面波型之影響，並進一步觀察粒子運動軌跡與波-波能量交換是否有關連性，期望能藉由實驗結果更進一步暸解波浪之非線性交互作用。 <br> Abstract: Since the ocean activities become frequent, the safety of ocean structure becomes more important. However, the design of ocean structures is more difficult than the design of land structures due to the complicated exerting wave forces, especially the nonlinear wave forces. Recently, researchers have strived for developing theoretical nonlinear wave model. Since the physical mechanism of nonlinear gravity waves is so complicated, the accuracy of the models still needs to be improved. This research is going to investigate this complicated problem. This research is a two-year project. The project experiments are conducted at the Fundamental Fluid Dynamics Laboratory in the Department of ESOE, NTU. The main facilities include a programmable piston-type wave maker, a wave flume with dimensions of 20m*0.3m*0.6m, a NI AT-AO-6 analog output, a Spectra-Physics Stabilite 2017-04S argon laser and a Kodak MotionCorder Analyzer Model SR-Ultra high speed camera. The 4-W argon laser and the high-speed MotionCorder are used to establish a particle image velocimetry (PIV) measurement system. Using this method, we can measure and observe the particle orbits in water. The first-year research topic is focused on using the PIV system to measure the particle trajectories in deep, intermediate, and shallow water waves under different incident conditions with various ka values. The measured particle trajectory data are verified by comparing with the data calculated using the linear wave theory, Stoke 2nd order wave theory, and Cnoidal wave theory. The mass transports due to different incident conditions will be calculated. The second-year research topic is focused on particle orbit patterns under wave-wave interactions with different incident ka parameters. Different incident wave conditions will be examined to investigate the relationship between particle motions and the surface profiles. The relationships between energy transfers and particle motions will also be examined.粒子軌跡非線性重力波浪質量傳輸非線性參數Particle trajectoriesnonlinear gravity wavesmass transportnonlinear parameter