本研究探討金屬平板(紅銅)在邊界條件為完全固定下，於穿音速流場中之流固耦合現象。兩種平板配置：1. Clean geometry以及2. Post in the middle於馬赫數為0.8, 0.9條件下之流固耦合實驗於成大航太研究中心（ASTRC）穿音速風洞進行測試並與雙向流固耦合（FSI）數值模擬結果進行比較。起初理想化的條件設定（材料參數、理想邊界條件、忽略重力影響…）結果指出在長厚比0.45% 、Clean geometry 配置，以及長厚比0.53% 、Post in the middle配置下之金屬板產生之結構震盪最為不穩定，其前兩個震盪模態之頻率非常接近並且擁有相近的能量分佈，被視為一種可能的震盪機制。進一步與實驗結果比對顯示實驗中的位移幅度比模擬結果小一個量級，表明雙向流固耦合模擬應該考慮到風洞全尺寸模擬、實際的平板固定方式、內艙的形狀以及風洞流場的背景噪音。靜態流場測試使用了kulite壓力感應器和PSP進行多點以及全平板面的壓力量測，其結果指出流場壓力大致平均分布然而流場卻非對稱。最後比對結果顯示在clean geometry配置下大致位移趨勢仍然與實驗相符，然而post geometry配置下，由於實驗技術原因，其結果之比對差異較為大，有待之後進一步研究。最後總結，實驗與模擬在平板的位移幅度以及振動頻率位移的比對上大致是相符合。

In this work, transonic fluid-structure-interactions of a copper compliant panel clamped on all edges was studied numerically and experimentally at Mach 0.8 and 0.9. The aforementioned configuration and a modified version with a single support, or post, in the middle were both tested in Aerospace Science and Technology Research Center (ASTRC) transonic wind tunnel under nominal condition: M=0.8, 0.9. Fully coupled flu-id-structure interactions (FSI) numerical simulations were also performed to simulate the experiments. The initial work on idealized panel (nominal material properties, ideal boundary conditions and flow domain) suggested that the with-post configuration is clos-er to flutter by modal coalescence for a thickness-to-length ratio of 0.53%, while the clean configuration has a critical thickness of 0.45%. Comparison with experiments, however showed large discrepancies in terms of maximum deflection, indicating that the FSI simulations should take into account of the actual geometry of the panel support, test-section geometry, cavity shape and noise in the flow. Static tests with kulite pressure transducers sensor and pressure-sensitive paint (PSP) revealed a roughly uniform pres-sure distribution within a 5% spatial variation, but also flow asymmetry. Clean geometry experiment agreed well with the simulations, however the experiment with a central post underwent to technical problem and will be redone in the future. Overall there is a good agreement between simulations and experiment in terms of amplitude and natural fre-quency shift induced by the flow.

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