The experimental and numerical investigation of a coaxial swirl injector, part of a multi-element injector head designed to equip a 30daN thrust rocket engine, is presented. The rocket engine is designed to function using LOX as oxidant and LCH₄ as fuel. The LCH₄ will be used to cool the combustion chamber walls, and thus the fuel will reach the injector head in a gaseous state. Two injector configurations have been proposed, one having 4 tangential channels for the oxidizer, and one having 6 tangential channels. The injectors testing assembly were first made by additive manufacturing using a 3D resin printer. In the next stage, in order to perform tests at pressures higher than 3 bar, the testing assembly was made of stainless steel, and the injectors were made of Inconel by additive manufacturing using the selective laser melting technology. The impact of the surfaces' roughness upon the spray cone angle has been observed. The mass flow curves and cold flow discharge coefficients C_d for the proposed injectors have been assessed using water instead of LOX. Numerical simulations have been carried out using ANSYS CFX.

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同轴旋流喷射器的设计、试验和数值研究

介绍了同轴涡流喷射器的实验和数值研究，它是设计用于装备 30daN 推力火箭发动机的多元件喷射器头的一部分。火箭发动机设计为使用 LOX 作为氧化剂和 LCH ₄作为燃料。LCH ₄将用于冷却燃烧室壁，因此燃料将以气态到达喷射器头部。已经提出了两种喷射器配置，一种具有4个用于氧化剂的切向通道，另一种具有6个切向通道。喷油器测试组件首先是使用 3D 树脂打印机通过增材制造制造的。在下一阶段，为了在高于 3 bar 的压力下进行测试，测试组件由不锈钢制成，喷射器由 Inconel 制成，采用选择性激光熔化技术通过增材制造。已观察到表面粗糙度对喷射锥角的影响。质量流量曲线和冷流量排放系数C _d建议的喷射器已使用水代替 LOX 进行了评估。数值模拟已使用 ANSYS CFX 进行。