液旋噴注器之間的交互作用對燃燒室及噴注盤的設計甚為重要，本研究為了瞭解其詳細交互作用，透過冷流觀察及熱燃點火實驗分析探討噴注器於不同相對位置時的交互作用，以提出較佳的設計方案。液旋式噴注器因其液旋特性，導致火焰分布不均，且在熱燃點火實驗時會噴出尚未氣化之推進劑。本研究改變噴注器間距(X/R = 2.6, 3.0, 4.0)，以水作為冷流實驗流體觀察三噴注器噴注之交互作用對於液體推進劑分布影響；實驗觀察到尚未霧化之液膜會因為互相撞擊導致液膜提早破碎，原先單噴注霧化之空心區域在交互作用後會出現液滴分布，使得噴霧分布均勻度提升。本研究亦以W2JP與過氧化氫搭配具壓力噴嘴之液旋式噴注器組合而成的噴注盤進行熱燃實驗；由於本實驗條件設定在富油(Fuel Rich)條件下，互相靠近時三噴注器排列下交互作用會有尚未氣化之過氧化氫穿透，破壞螺旋結構，造成火焰中心局部混合比提高，燃燒反應較劇烈，OH*螢光強度提高；當三噴注器距離過近時(X/R = 2.6)因為燃燒反應較劇烈，高溫氣體產生量較大，也因此具較快的軸向速度，故熱釋放率最高位置出現在較下游處。在本研究的實驗範圍內，噴注器交互作用後可重新調整OH*之分布狀態，噴注器中心間距為21 mm(X/R = 3.0)之排列為目前實驗顯示火焰分布最為均勻，是較適當之排列方式。

The interaction between liquid cyclonic injectors has a significant impact on the design of the combustion chamber and the injector plate. Therefore, this study aims to understand the detailed interaction between these injectors through cold flow observation and thermal ignition experiments, analyzing the interaction of injectors at different relative positions to propose optimal design solutions.
The liquid cyclonic injectors, due to their swirling characteristics, result in uneven flame distribution. Additionally, in the thermal ignition experiments, there is the issue of spraying unvaporized propellant. In this research, the injector spacing (X/R = 2.6, 3.0, 4.0) was varied, and water was used as the cold flow experimental fluid to observe the effect of interaction between three injectors on the distribution of liquid propellant. The experiments revealed that the non-atomized liquid film would break prematurely due to mutual collisions, and after interaction, the previously hollow area from a single atomized injection would exhibit a distribution of liquid droplets, thereby enhancing the uniformity of spray distribution. Furthermore, this study also conducted thermal ignition experiments using a injector plate composed of W2JP and hydrogen peroxide combined with pressurized nozzles. Given that the experimental conditions were set under fuel-rich conditions, when the three injectors were positioned closely together, the interaction led to the penetration of unvaporized hydrogen peroxide, disrupting the spiral structure. This resulted in an increased local mixture ratio at the flame center, leading to more intense combustion reactions and higher OH* fluorescence intensity. When the three injectors were positioned very closely (X/R = 2.6), the more intense combustion reactions led to a larger production of high-temperature gases and consequently a faster axial velocity, causing the location of the highest heat release rate to appear downstream. Within the scope of this study's experiments, the interaction between injectors could readjust the distribution state of OH*. Among the studied arrangements, the one with an injector spacing of injector centers are 21 mm apart (X/R = 3.0) exhibited the most uniform flame distribution, making it a more suitable configuration.

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