懸臂梁的振動特性與其所沉浸的流體性質有極大的關係，本文以二維流場解析結果得知流體與懸臂梁沉浸部分之交互作用，建立完全或部分沉浸下懸臂梁受外力激發的位移響應分析，並將流體性質、結構尺度、沉水率對共振頻率的影響以折減曲線表示。同時可以利用此折減曲線與懸臂梁位移響應來反推沉浸流體的黏滯係數。在有限元素模擬的數值分析中，採用兩種技巧，分別為附加質量與聲學阻抗法，取代直接使用流體元素將流-固交互作用加入，以節省計算成本。特別是聲學阻抗法能且使用於三維結構上。對於模擬完全或部分沉浸的複雜結構物之位移響應較為容易。

The vibration characteristic of a cantilever beam strongly depends on the properties of the fluid in which the beam is immersed. By the analytical results of two-dimensional flow analysis, we could clarify the interaction between fluids and the submerged cantilever beam. In this thesis, we established the method to analyze the displacement response of a fully or partially submerged cantilever beam due to an external excitation force. The influence of fluid properties, structure dimensions, and submerged percentage on the resonant frequency are shown on the reduction curves. These reduction curves can also be used to back-calculate the dynamics viscosity of an immersing fluid from the vibration response of a cantilever beam.
In our numerical analysis of finite element simulations, we applied two techniques, which are Added Mass and Acoustic Impedance, to add the fluid-structure interaction instead of using fluid elements directly for saving computational cost. Particularly, Acoustic Impedance method is applicable to three-dimensional structures. It is easier for simulating the displacement response of a fully or partially submerged complex structure.

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