煤油與過氧化氫的推進劑組合具有低成本、低毒性、較佳的儲存特性、並具備不錯的推進性能，在火箭推進上具有應用前景。由於煤油與過氧化氫之組合本身不具自燃特性，所以本研究研發出可與過氧化氫接觸時自燃的煤油基的燃料（W2）。此燃料是通過將多種催化劑、中間介質和煤油結合調配而出，其具高熱值（ΔH = 32.5 kJ/g）且可與過氧化氫互溶並呈現自燃特性，在液滴接觸測試中，記錄W2和過氧化氫的自燃點火過程並探討動量變化造成接觸面積變化，進而影響點火延遲之原因。針對煤油與過氧化氫高混合比的操作特性，本研究亦提出了二階段衝擊式噴注器設計（O-F-F-O），其中過氧化氫和煤油分別形成O-O與F-F噴霧再進行混合。在本研究中，使用PLIF技術觀測個別噴霧液滴於空間中的分布，並在混合比3.75至6.25的範圍內進行研究，探討了兩階段衝擊式噴注器模組的衝擊距離、角度和噴注速度等設計參數對噴霧分布的影響。在假設噴霧間無交互作用的條件下，對個別燃料和氧化劑噴霧進行機率分布疊合進行預測其混合後的分布，並將其結果與實際二階段式O-F-F-O噴霧的實際分布進行比較。由於W2/過氧化氫的自燃延遲時間相對於聯氨基的自燃推進劑系統為長，在開放空間下以衝擊式噴注器噴注時自燃點火條件較嚴苛，故本研究設計了預混式雙推進劑噴注器，並稱為液旋式噴注器，以獲得穩定的自燃點火。在此噴注器中，液體燃料和氧化劑以切向方向噴射到空腔中進行接觸混合，提供液體觸媒反應的時間，而形成的中心空腔空間則容納氣化的推進劑，以進行氣相反應達到自燃點火溫度。在熱燃實驗中針對噴注器自燃點火延遲操作限制進行討論，並通過實驗評估和驗證了噴注器的設計和性能。

The combination of kerosene with hydrogen peroxide is more promising due to its low cost, low toxicity, long storage capacity, and adequate propulsive performance. Due to the fact that the combination of kerosene and hydrogen peroxide does not possess inherent hypergolic characteristics, this study also formulates a kerosene-based fuel (W2) that exhibits autoignition when in contact with hydrogen peroxide. W2 and hydrogen peroxide present an ignition delay time of 20 ms in droplet contact test. The high heating value (ΔH = 32.5 kJ/g) fuel is prepared by combining several catalysts, promoted mediums, and kerosene to make it miscible and hypergolic with hydrogen peroxide. In terms of high mixture ratio issues, a procedure of two-stage, like-doublet (O-F-F-O) impinging-jet injector design is presented, where mixing of H2O2 and kerosene occurs between O-O and F-F sprays. Investigations at O/F ratios between 3.75 and 6.25 are performed. The impinging distance, angle, and jet velocity of the two-stage impinging-jet module are the design parameters examined. The PLIF technique is used to observe the spatial droplet distribution of the individual spray. The predicted mixing behavior obtained by overlapping the individual fuel and oxidizer sprays is compared to the actual mixing of the O-F-F-O spray to justify the spray / spray interactions. Due to the longer hypergolic ignition delay time of the W2/hydrogen peroxide system compared to the traditional hypergolic system using hydrazine-base propellant, the conditions for hypergolic ignition in an open space are more stringent when using an impinging injector. A premixed type bipropellant injector design, namely liquid-cyclonic injector unit has been designed to obtain auto-ignition capability. Liquid fuel and oxidizer are tangentially injected into the small chamber to mix and provide the period for liquid catalytic reaction, and the formed hollow center space holds the vaporized propellant to perform gas-phase oxidation reactions to its autoignition temperature. In the hot-fire experiments, the auto-ignition behavior and the operation limits of injectors are also discussed. The combination of W2 with hydrogen peroxide shows promise as a green propellant system, and the design and performance of the injector are evaluated and validated through experiments.

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