Influence of coupling schemes of radial and circumferential flame stabilization modes on flow and combustion characteristics of compact combustion for gas turbine

The combination of the strut and cavity is a common structural configuration for ultra-compact combustor in the gas turbine. The streamwise vortices inside the cavity play the role of stabilizing the flame and mass exchange in the spanwise direction, which is very important for the compactness and ignition performance. In this paper, the numerical simulations and the experiments were performed to study the influence of the combustor strut blocking ratio, cavity length-to-depth ratio, and strut inclination angle on the flow, the streamwise vortices distribution, as well as the combustion characteristics. We also discussed the generation of streamwise vortices and the effects of streamwise vortices on the flow and combustion performance. The results showed that the strut blocking ratio and cavity length-to-depth ratio mainly affect the strut recirculation zone and the cavity recirculation zone, the interaction of which is the key to the generation of the streamwise vortices. The reasonable distribution of the streamwise vortices promotes the mass exchange and the uniformity of the temperature distribution. In addition, the strut inclination angle has a great influence on the flow characteristics, and the forward-inclined strut is more conducive to combustion. Based on the obtained conclusions, a new design of ultra-compact integrated combustor is proposed, and it has improved flow and combustion performance.