Combustion Instability and LES Analysis in Hybrid Rocket Motor
Combustion tests were conducted in a hybrid rocket motor with a PMMA/GOX combination to study the possible interaction between acoustic perturbations due to a vortex shedding and an unsteady heat release on the non-linear combustion. Pressure measurement data showed that a sudden pressure drop of about 10 psi occurred during the nominal combustion only when disk 4 was used. This peculiar discontinuity in pressure signal is thought to be described by a negative DC-shift and it is conjectured that the perturbation generated by disk 4 located in the prechamber may be out of phase with the that of the shedding vortex produced in the post chamber. In order to understand the dynamic role of vortex shedding process, a numerical study with LES technique was performed in a duct flow with wall blowing. The turbulent structures were investigated in the context of the formation of roller-like vortices, kinematic modification of nearwall coherent structures, and the existence of periodic oscillatory flow having an instantaneous large negative velocity. Even though it is expected that the excursion to negative velocity may significantly influence on the temperature fluctuation near the wall surface, its mechanism is not fully understood yet and it should be further pursued in the future study.
hybrid rocket DC-Shift turbulent flow wall injection compressible flow
Kim Bohoon Lee Changjin Yang Na
Department of Aerospace Engineering, Konkuk University, Seoul 143-701, Korea Department of Mechanical Engineering, Konkuk University, Seoul 143-701, Korea
国际会议
2010 Asia-Pacific International Symposium on Aerospace Technology(2010 亚太航空航天技术研讨会 APISAT 2010)
西安
英文
367-370
2010-09-01（万方平台首次上网日期，不代表论文的发表时间）