TITLE:
A Study on the Performance of a New-Type Swirl-Stabilized Combustor for Enhancing Boiler Low-Load Stable Combustion Capability
AUTHORS:
Hongjun Li
KEYWORDS:
Swirl-Stabilized Combustor, Interstitial Air, Low-Load Combustion Stability, Gas-Particle Flow Properties, Central Recirculation Zone
JOURNAL NAME:
Energy and Power Engineering,
Vol.18 No.8,
August
3,
2026
ABSTRACT: This study experimentally investigates the gas-particle two-phase flow characteristics of an old-model burner (OMB) and a new-type swirl-stabilized combustor (NTSTC) designed for a 350 MW opposed-fired coal boiler. Using a particle dynamic anemometry (PDA) system, the three-dimensional velocity field, turbulence intensity, and particle volume flux at the burner outlet were measured at nominal load cases spanning 20% - 100%. The results show that the NTSTC forms a distinct central recirculation zone (RZ) in the near-nozzle region (x/d = 0.1 - 0.5), where the axial velocity exhibits a bimodal distribution and the radial velocity indicates centripetal particle movement near r/d ≈ 0.2. These characteristics persist at low loads and promote particle residence and central accumulation. Compared with the OMB, the NTSTC exhibits higher turbulence intensity within central RZ and stronger gas-particle mixing, including 20% load. The particle volume flux results further demonstrate central particle enrichment and particle backflow within the RZ. Overall, the NTSTC provides more favorable near-field gas-particle flow organization and better aerodynamic adaptability to load variation. The present study is limited to cold-flow measurements; combustion efficiency, gas composition, and NOx emissions were not directly evaluated.