中心支板参数对 RBCC 发动机性能影响研究

Focusing on the critical geometric parameters settings of the RBCC central-strut under a wide-speed acceleration mission, the effects of parameters such as blockage ratio, strut angle and aspect ratio on the performance characteristics of the engine in terms of ejector, ramjet/scramjet modes were studied by using the full-channel integrated numerical simulation method within the speed range of Ma0.4~6. The results show a significant effect of compression on the air flow in each mode, which in turn contributes to a more sufficient combustion reaction as the ratio of blockage increasing, and the total thrust is improved by 0.13%~5%. With the increase of the strut angle, except for the shock wave caused by the change of flow path cross section configuration at Ma2.5, the enhanced leading shock of the strut makes the combustion reaction position more concentrated. Meanwhile, the fuel injection penetration is much deeper and the full combustion heat release makes the total thrust of the engine improved by 2.2%~5.7%. As the aspect ratio decreasing, under the flight condition of Ma0.4~4, the increased flow path area is beneficial to the lateral expansion of kerosene, and the better oxygen-fuel mixing ele- vates the total thrust of the engine by 0.2%~5.8%. However, at the speed of Ma6, the deceleration and pressurization of the shock wave at the front edge of the strut gradually weakens and the total thrust is reduced by 5.2%~7.1%.