Abstract: An improved method and apparatus for actively controlling a combustion process such as a waste incinerator by means of a spatial and temporal synchronized injection of fuel. The improved method and apparatus employs an active control system which controls the intentional formation of large scale, coherent vortices and the synchronized injection of the fuel supply at various locations relative to the formation of the vortices. The preferred apparatus comprises an actuator or similar structure that is adapted for producing and stabilizing discrete, large scale vortices in a combustion device. In addition, another device controls or modulates the injection of the fuel into the vortices at the optimal location and timing relative to the vortex cycle. As applied to an incinerator, this method can be optimized to ensures that the fuel and waste are introduced into the highest temperature locations, were extended residence times are obtained by trapping the fuel and waste inside the vortices.