The influence of pylon and wall injection in coaxial jets of a Dual Combustion Ramjet engine is numerically investigated in a non-reacting flow field. The supersonic combustor is modeled and analyzed using the commercial CFD software ANSYS 18.0. The three-dimensional compressible Reynolds-averaged Navier-Stokes (RANS) equations coupled with the SST k-ω turbulence model have been used to analyze the coaxial mixing characteristics of the jets. The numerical study is validated with the experimental data of the wall static pressures measured in the combustor’s flow direction. The pylon and wall injectors are located symmetrically at the gas generator’s exit nozzle, and the air is used as the injectant to simulate gaseous fuel. Three injection pressures are used for the study to understand the flow field characteristics in the injector regime. Also, the gas generator downstream direction is investigated. The shock waves generated from the gas generator nozzle enhance the mixing of the coaxial jets with minimum total pressure loss. The shock wave interactions are noticed with reducing intensity within the supersonic combustor for pylon injection, leading to higher total pressure loss than the wall injection. The pylon injection provides the spatial distribution of fuels compared to the wall injection in the coaxial supersonic flow field.

在非反应流场中，数值研究了塔架和壁喷射对双燃烧冲压发动机同轴射流的影响。使用商业CFD软件ANSYS 18.0对超音速燃烧器进行建模和分析。三维可压缩雷诺平均Navier-Stokes（RANS）方程与SST k耦合-ω湍流模型已用于分析射流的同轴混合特性。数值研究得到了沿燃烧室流动方向测得的壁静压力的实验数据的验证。挂架和壁式喷射器对称地位于气体发生器的出口喷嘴处，并且空气用作喷射器以模拟气态燃料。三种注入压力用于研究，以了解注入器状态下的流场特性。另外，研究了气体发生器的下游方向。从气体发生器喷嘴产生的冲击波以最小的总压力损失增强了同轴射流的混合。在注入塔时，超声波燃烧器内的冲击波相互作用降低了强度，导致总压力损失比壁式喷射更高。与同轴超音速流场中的壁式喷射相比，塔式喷射提供了燃料的空间分布。