衝擊式霧化器常用於液態火箭噴注器設計上，能使推進劑適當的霧化與混合。在傳統上，噴注盤上噴孔的排列僅以方便製造及幾何上的均勻排列為主，並未細究各個噴流之間的霧化混合關係。實際上，實驗觀察經衝擊所形成的各股噴霧會互相影響。本研究係應用兩組相同之全發展雙衝擊噴霧，改變其相互距離，實驗觀察並分析探討噴霧與噴霧間交互作用的特性。
本研究應用PLIF(Planar Laser-Induced Fluorescence)技術、粒徑量測儀、PIV(Particle Image Velocimetry)等技術，進行噴霧的實驗分析觀察。實驗觀察顯示，一股噴霧若與另一股噴霧直接接觸，原噴霧液滴空間分布驅寬且較為均勻，液滴粒徑分布也變小。經分析計算液滴運動之相對韋伯數，得知液滴碰撞情形應為拉伸式碎裂為主，且估算碰撞機率相對低，無法解釋觀察現象，驗證全發展之衝擊噴霧間之相互作用，以液滴運動所帶動之氣流牽引為主。

Impinging type injector has been commonly adopted in liquid rocket injector plate design because it simultaneous atomizes and mixes propellants adequately. Conventionally, the arrangement of impinging injectors on injector plate considers the geometry uniformity and manufacture convenience, the interactions between sprays were hardly an issue to be considered in design. In practical, experimental result reveals that the interactions between sprays do occur. This thesis research utilized a pair of identical impinging sprays, by changing their distance, experimental observations and analyses have been performed to characterize the interactions between sprays.
This research utilized PLIF (Planar Laser-Induced Fluorescence) technique, Malvern droplet analyzer, and PIV (Particle Image Velocimetry) for spray analysis. The results show that the mass distribution becomes wider and more uniform, and mean droplet size distribution gets smaller when two fully developed sprays are in direct contact. By calculating the Weber number between droplets in the interaction zone, it shows that the outcome of droplet collisions, although low in probability, is mainly in stretching separation, which cannot explain the experimental observations. The major interaction between sprays is justified to be the sucking effect of the airflow driven by droplet motion in individual spray.

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