This paper presents a simulation-based solution for calculating rocket engine performance with liquid-type propellants of Paraffin and Kerosene for oxidizer to fuel ratio that is given by a linear formula. The engine was divided into two main stages: combustion chamber and a nozzle. In the first phase, conditions were found in the combustion chamber, based on the assumption of equilibrium according to Barrere. Next, the flow in the nozzle was calculated based on the fluid in the combustion chamber. Three main theories were examined in order to find the flow conditions in the nozzle: equilibrium, frozen and mixed flows (Bray conditions). While the latter assumes the existence of the “Sudden Freezing Point” found by Bray, so that from this point to the end of the nozzle, the flow is assumed to be frozen. The use of the proposed simulation might contribute for multiple calculations performance (e.g., fuels with multiple intermediate reactions). Comparison between both types of fuels/propellants for the three described types of flow is presented alongside CEA software results, whereas good agreement between solutions was found. Also, the greater the ratio between hydrogen and carbon atoms, the better the engine performance for a particular oxidizer. Finally, it was found that an equilibrium flow model throughout the nozzle has a better nozzle performance compared to the other types of flows.

中文翻译：

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含石蜡/煤油推进剂的火箭发动机喷嘴反应流的求解

本文提出了一种基于模拟的解决方案，用于计算使用石蜡和煤油液体推进剂作为线性公式给出的氧化剂燃料比的火箭发动机性能。发动机分为两个主要阶段：燃烧室和喷嘴。在第一阶段，根据 Barrere 的平衡假设，在燃烧室中找到条件。接下来，根据燃烧室中的流体计算喷嘴中的流量。为了找到喷嘴中的流动条件，研究了三种主要理论：平衡流、冻结流和混合流（布雷条件）。而后者假设存在布雷发现的“突然冻结点”，因此从该点到喷嘴的末端，流动被假设为冻结。使用建议的模拟可能有助于多种计算性能（例如，具有多个中间反应的燃料）。与 CEA 软件结果一起展示了两种类型的燃料/推进剂对三种描述的流动类型的比较，同时发现了解决方案之间的良好一致性。此外，氢原子和碳原子之间的比率越大，特定氧化剂的发动机性能就越好。最后，发现整个喷嘴的平衡流动模型与其他类型的流动相比具有更好的喷嘴性能。而在解决方案之间找到了很好的一致性。此外，氢原子和碳原子之间的比率越大，特定氧化剂的发动机性能就越好。最后，发现整个喷嘴的平衡流动模型与其他类型的流动相比具有更好的喷嘴性能。而在解决方案之间找到了很好的一致性。此外，氢原子和碳原子之间的比率越大，特定氧化剂的发动机性能就越好。最后，发现整个喷嘴的平衡流动模型与其他类型的流动相比具有更好的喷嘴性能。