Numerical and experimental investigation on flow field and combustion characteristics of strut with cavity configurations in a practically constrained channel

The performance of integrated strut with radial cavity flameholder may be affected by complex flow characteristics within the corner region boundary. However, the effect of channel boundaries on cavity flow structure and flame stabilization of strut with radial cavity is still not clear. In this investigation, the flow fields in the cavity near corner region were investigated through combined numerical simulations and experimental investigations. The results suggested that significant impacts of corner region boundary layer disturbances on recirculation zone stability were identified, which included structural deviation and disruption of the recirculation zone. Building upon this foundation, this investigation applied a vertically intersecting cavity configuration for the strut to mitigate the detrimental effects of the corner region boundary layer on cavity flame stabilization in practically constrained channel. Experimental and numerical investigations of flow fields suggested that the vertically intersecting cavity configuration significantly enhanced recirculation zone stability in the cavity near corner region. The combustion experiments and numerical simulations revealed that the vertically intersecting cavity configuration exhibited not only a more uniform temperature distribution but also superior mixing performance within the cavity. The novel configuration achieved 3–5 % better combustion efficiency and limited the degradation of the total pressure recovery coefficient to less than 1.5% compared to the strut with radial cavity configuration. This investigation can provide numerical and experimental data as well as preliminary theoretical references for the subsequent design and application of strut with cavity flameholders.