Investigation of Flow Field Characteristics in RQL Combustor

Visualization investigation with PIV (Particle Image Velocimetry)for an annular RQL (Rich burn-Quench-Lean burn) combustor was conducted under non-reacting conditions.The influences of momentum flux ratio and main flow Reynolds number on the flow field and downstream swirl flow were investigated.The experiment was carried out at atmospheric pressure condition with both mainstream and quenching jets with temperature of 25℃.Several distinct results were concluded.With a constant mainstream Reynolds number, increase in momentum flux ratio results in significant change of the recirculation zone size, with the length decreasing and the width increasing, leading to the shape of recirculation zone altering from conical to cylindrical.(Quenching jet also influences the downstream swirl flow; with the increase of momentum flux ratio, the downstream swirl flow will be destroyed gradually while the mainstream Reynolds number remains constant.Nevertheless, the mainstream Reynolds number has no evident effect on recirculation zone size or downstream swirl.)