本論文研究剛性機翼在穿音速流中振動之動力學，研究重點主要在震波不穩定性，它是由震波與流場分離相互作用引起的，進而導致作用在機翼上的氣動力快速振動。透過穩態和暫態的靜止結構電腦數值模擬發現，機翼在±15°有兩個穩定的平衡點，與實驗結果±14°非常接近，驗證了數值分析的準確性。而背景紋影技術用於流場及震波可視化，其實驗結果與數值模擬於膨脹波和λ震波具有高度吻合性。此研究還探討了震波引起的振動頻率，結果顯示觀察到的值約為70和100赫茲與其他研究結果相似。而另一個250赫茲係由實驗中壓克力板的變形所引起。此外，另一頻率在330赫茲可能是由於機翼自然頻率引起的。

This study investigates on the dynamics of a rigid wing oscillating in a transonic flow, with a focus on shock instability, which is caused by shock waves interacting with flow separation, leading to rapid fluctuations in aerodynamic forces acting on the wing. Through static-steady and static-transient CFD analysis, the wing was found to have two stable equilibrium points around ±15°, which closely matched experimental results of ±14°, validating CFD predictions. Background-oriented schlieren (BOS) techniques were used to visualize shock waves, revealing expansion waves and lambda shocks that corresponded well with numerical simulations. This study also explores shock-induced oscillations frequencies, which shows the values around 70 Hz and 100 Hz were observed, consistent with prior studies. One high frequency at 250 Hz was attributed to an experimental deformation of the test setup. The other higher frequency at 330Hz could conceivably due to wing natural frequency.

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