近年來，混合火箭因其具備高機動性、高安全性以及低成本…等之優勢，使其在新興航太領域中，獲得相當多研究單位以及學者之重視，並積極研發相關技術以及應用於商業領域；然而，目前之混合火箭多應用於前瞻或者任務型探空火箭，此原因是由於混合火箭之推進性能無法有效地提升，另一方面，其重複點火能力也是一項須克服之難題，在上層火箭點火以及軌道轉換調整，都需要可靠之發動機重複點火技術才能達成，目前，相關之研發已經陸續進行，包含了前置觸媒床點火、消耗式觸媒床點火以及觸媒燃料點火，其中，前置觸媒床點火技術已經具有相當豐富之研究成果，同時也是目前大多過氧化氫混合火箭之點火方式，然而其觸媒之壽命以及前置觸媒床之機構重量，使此點火方式在應用上並無太大之優勢；因此本研究認為使用觸媒燃料點火之方式，不但能解決上述之缺點，並且在許多相關初步研究中，更指出添加之觸媒可幫助燃料退縮，進一步提升發動機之推進性能，然而，此類點火方式仍處於非常初步之研究階段，且對於此點火方式之過程和機制也尚未明瞭，就此，本研究致力於探討混合火箭異相觸媒自發點火之步驟與機制，並分析其點火特性以及相關之影響因素，對於未來觸媒燃料點火之研究建立基礎。
本研究將錳觸媒與乙烯粉末以一定比例混合並製成燃料藥柱，並使用高濃度之過氧化氫作為氧化劑，以直接噴注藥柱表面之方式進行點火，由於過氧化氫與固態觸媒在接觸時，會快速進行分解反應並釋放大量能量，此能量提供了藥柱表面之燃氣供給以及氧化劑之氣化，最後點燃藥柱；然而在本研究之實驗結果中發現，當藥柱表面開始出現燃燒現象時，流場之溫度並無太大之變化，溫度數據也遠低於火焰溫度，據此，本研究認為此時的燃燒反應僅維持在藥柱之表面上，由觸媒反應主導並提供能量維持反應，最後當整體燃燒室內溫度持續上升，且燃氣以及氣態氧化劑量足以維持氣相燃燒反應時，燃燒室內才發展出穩定的擴散火焰燃燒。
本研究藉由常壓之藥柱燃燒測試，在藥柱表面以及流場內裝備多支熱電偶並進行溫度量測，同時，利用藥柱成分之半透明性，以外部觀測之方式，紀錄火焰出現的時間點以及燃燒內燃燒反應的程度，再加以分析和討論，並以定性上的數據變化結果進行點火步驟之分析和定義；最後，本研究提出一符合觀測及量測結果之點火步驟，分為異相觸媒反應、過渡及氣相燃燒反應步驟，另一方面，為了近一步驗證此點火機制，本研究也特別針對兩大影響因素：燃料中觸媒含量以及氧化劑流量，進行實驗探討，本研究由實驗結果初步地了解其對於點火過程中的影響；這些初步之實驗成果以及相關之討論，將可提供未來觸媒藥柱自發點火式混合火箭發動機之設計參考和研究依據參考。

With the flexibility of throttling and multi-ignition, the hybrid rocket is considered as an advantageous system for orbital maneuver vehicle and complicated space mission. Nowadays, most of the hybrid rocket system was using an additional ignition device to start the motor, however, it also reduces reliability. On the other hand, the hypergolic hybrid rocket system can ease this issue and fulfill most of the performance requirements. In previous research, the hypergolic features are achieved by using the Mn-catalyst-added fuel, which is a combined mixture of polyethylene binder and manganese catalyst for the decomposition of oxidizer, and high concentration hydrogen peroxide as the oxidizer. Additionally, they also found that, by adjusting the oxidizer operating conditions and fuel grain configurations, three different kinds of ignition process were observed. In this research, a similar formula was used and further research on the ignition process was studied. By inserting several thermal couples into the fuel port, the temperature data of fuel surface and chamber flow field were measured and analyzed. It is found that there are mainly three stages during the ignition process and some characteristic temperature data are obtained. Furthermore, the influence of the oxidizer mass flow rate and catalyst percentage in fuel grain to the ignition process were also tested and studied. From the previous ignition process, we deduce that the ignition process would accelerate, especially in the catalytic reaction heating stage, by increasing the amount of catalyst and oxidizer. With the result of experiments and analyzes, this inference was fully verified.

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