Active Control of Combustion Instability in a Ramjet Using Large-Eddy Simulations

摘要

This study has developed a large-eddy simulation model for active control. Thebasic simulation control was extended for general applications, the simulation code was implemented on a massively parallel processor, and two active control techniques (acoustic feedback control and secondary fuel injection control) were investigated. However, the primary focus for active control in this study was on secondary fuel injection techniques, as it had been demonstrated in past experimental studies that this method was more practical. Numerical simulations of fuel injection control were carried out and, in addition, a theoretical model for secondary fuel injection control was developed along with a method to couple the theoretical model to the simulation model. Finally, to implement a robust controller, a fuzzy logic based controller for fuel injection was studied using a simplified problem geometry. To investigate the effects of three-dimensionality, full 3D LES of combustion instability was also carried out.