The phenomena of precessing vortex core (PVC), entrainment of particles from the ash hopper, and swing of the vortex end in swirling flow have a negative effect on flow field and separation performance of cyclone. In order to alleviate these negative effects, a strategy to improve flow structure by installing cylinder vortex stabilizer is proposed, and the effects of different size stabilizers on the performance of cydones are studied by experiment and CFD simulation. The results show that cylinder vortex stabilizer can improve the stability of the vortex in the cyclone, by reducing the impact of PVC, entrainment of particles from the ash hopper, and swing of the vortex end. This improves collection efficiency of fine particles, with an increase of 5.52% for particles whose diameters are smaller than 3 mu m. The stabilizer has little effect on the pressure loss of the cyclone, with an increase of only 3.61%. (C) 2020 Elsevier B.V. All rights reserved.