在超音速燃燒衝壓發動機中，由於氣流滯留於燃燒室的時間過短，因此在燃燒室內裝置駐焰機構，除了可提升燃料與氣流的混合效率外，也能增加燃燒的穩定性。支架為其中一種駐焰機構，該構型突入於流場中造成強烈的氣流擾動，但同時也造成一定程度的氣流總壓力損失。本實驗利用支架作為駐焰機構，並以前緣傾斜角35度、楔角18度的構型為基礎，固定厚度與高度，設計楔角(25度)改變，以及傾斜角(25度)改變之兩組構型，經由液態燃油JP4從頂部噴注於馬赫二流場，觀察與探討傾斜角與楔角改變，對燃料噴霧與氣流之間交互作用的影響。實驗結果顯示，傾斜角或楔角個別降低，會造成後緣頂部的氣流轉折角增加，進而促使尾部渦漩提升燃料噴霧與氣流之間的交互作用，增強氣/液混合效益;但同時傾斜角或楔角個別降低，反致尾部渦漩的強度減弱而降低混合效益。此外，相比於楔角改變，傾斜角改變對燃料與氣流混合效益的影響較明顯。綜合上述，藉由調整前緣傾斜角與楔角，找到後緣頂部之氣流轉折角，以及尾部渦漩之強度，彼此之間的平衡點，以獲得最佳的燃料與氣流混合效益。

The short residence time of supersonic airflow in the combustor of Scramjet makes it hard to perform fuel/air mixing properly and achieve flame stabilization. Therefore, Flame-holder installed in the combustor is a general solution. In the research, the strut with 35 degrees tilt angle and 18 degrees wedge angle of the leading edge is used as the basic configuration. Under the same height and thickness, one with a different wedge angle (25 degrees) and the other with a different tilt angle (25 degrees). The research is conducted by a reflected shock tunnel which produces Mach 2 airflow and required conditions. JP-4 fuel is injected laterally into supersonic airflow from the top of the strut. The experimental results show that with the tilt angle or wedge angle decreases, the airflow turning angle at the top of the trailing edge increases, while the intensity of the vortex in the wake region decreases. These two affect the mixing between fuel spray and airflow. Therefore, the best fuel/air mixing can be obtained by adjusting the tilt angle and the wedge angle of the leading edge to find the balance point between the airflow turning angle at the top of the trailing edge and the intensity of the vortex in the wake region.

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