超燃衝壓引擎的燃燒室氣流速度為超音速，為了達到在超音速氣流中成功點火燃燒的效果，必須使用駐焰器來產生低速迴流區，為燃燒室提供可穩定駐焰之區域。侵入式支架駐焰器可避免燃燒過於靠近壁面，又有利於熱量傳遞於燃燒室，但由於總壓損失的影響，支架厚度有所限制，導致燃料混合能力較差。因此本實驗將支架駐焰器前後分離，形成分節支架來製造額外的迴流區，並利用紋影視流法與粒子影像測速系統，觀察不同幾何構形參數對分節區域之迴流結構影響。
本研究使用視流紋影系統於震波風洞中，進行分節支架駐焰器之震波結構的觀測，並利用粒子影像測速系統（Particle Image Velocimetry，PIV）觀察分節區域的迴流結構，風洞可運作時間約為0.8 ms，實驗開始前使用流體化床預先將示蹤粒子流化，使粒子與氮氣充分混和後投入自由流流速為馬赫數2的測試段中，再通過邏輯閘控制高速攝影機及兩道雷射之時序拍攝出能進行 PIV 運算之時間間隔約為500 ns的兩張瞬時影像，並透過PIVlab進行速度場計算。對L/D=2、3、4 之不同楔面角度θwe=25°、15°之分節支架駐焰器流場觀測分析後，成功發現不同設計參數對於分節支架駐焰器流場的影響。
在L/D=2條件下，楔面角度對震波結構震盪無顯著影響，但對迴流區結構有明顯差異。當楔面角度θwe=25°時，迴流區流動穩定，且於靠近剪切層處有氣流交換流動現象，有助於氣流交換與混合。相比之下，θwe=15°時，迴流區結構凌亂且流動不穩定，因較小角度減少氣流減速與膨脹效應，導致內外壓力差較高，進一步擾亂了逆向流場。在L/D=3條件下，震波結構較L/D=2時更不穩定，楔面角度仍顯著影響迴流結構。當楔面角度θwe=25°時，迴流結構穩定，逆向流與剪切層交錯流動分佈更廣泛。當θwe=15°時，流場更不穩定，因較大壓差，氣流提前進入迴流區，破壞迴流結構，導致分節區形成兩個分別流動的低速區域。在L/D=4 條件下，震波結構極不穩定。當楔面角度θwe=25°時，迴流結構類似L/D=2、3，但膨脹效應使氣流撞擊後壁面更強烈，逆向流更快速，剪切層和高速逆向流使迴流區不穩定。當θwe=15°時，主流場與分節區壓差大，高速氣流向內轉折並形成尾流撞擊後壁面，導致前後分離的低速區，上下高速氣流匯聚，完全破壞迴流區結構。
本研究為分節支架的優化設計和實際應用提供了重要依據，並為未來的燃料噴注與熱燃研究提供實驗設計方向，透過未來進一步研究可提升分節支架駐焰器的效率和可靠性，實現更佳的流場控制和燃料混合效果。

In supersonic combustion ramjet (scramjet) engines, achieving successful ignition and stable combustion in supersonic airflow necessitates the use of flameholders to create low-speed recirculation zones. Intrusive strut flameholders prevent combustion from occurring too close to the walls and enhance heat transfer within the combustion chamber. However, their thickness is limited due to total pressure loss, resulting in poor fuel mixing. This study explores the effect of segmented strut flameholders, designed to create additional recirculation zones, on the flow field. Using schlieren imaging and Particle Image Velocimetry (PIV) in a shock tunnel, the study observes shock structures and recirculation zones at various geometries. Tests were conducted at L/D ratios of 2, 3, and 4 with wedge angles (θ_we) of 25° and 15°.
Results indicate that while wedge angles do not significantly impact shock oscillations at L/D=2, they do affect recirculation structures. At θ_we=25°, the recirculation zone is stable and aids in airflow mixing, whereas at〖 θ〗_we=15°, it becomes unstable due to higher pressure differences. At L/D=3 and L/D=4, shock structures are more unstable. At θ_we=25°, stable recirculation is observed but with intensified interactions at higher L/D ratios, leading to instability. Conversely, at θ_we=15°, high-speed airflow converges, disrupting the recirculation zone. This study provides a basis for optimizing segmented strut flameholders, offering directions for future fuel injection and combustion studies to enhance their efficiency and reliability for better flow control and fuel mixing.

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