Based on the computational particle fluid dynamics(CPFD) method

numerical simulation on particle flow characteristics of a 350 MW unit supercritical circulating fluidized bed(CFB) boiler is carried out. The flow characteristics of particles and particle clustering in the CFB boiler and the change laws with the height of the furnace and operating conditions are mainly studied. Moreover

the simulation results are compared with the field test results

which verifies the reliability of the simulation. The results show that

along the width of the furnace

the axial movement speed of the particles presents an uneven distribution of high in central area and low in near-wall area

while the particle mass concentration and particle cluster volume fraction present the characteristics of small in central area and large in near-wall area. Along the furnace height direction

as the height increases

the particle mass concentration rapidly decreases from 140 kg/(m2·s) to 4 kg/(m2·s). The axial movement speed of particles in the center of the furnace increases faster than that in the area near the wall. The increase of the circulation volume and the decrease of the primary fluidization wind speed will reduce the axial movement speed of the particles and increase the volume fraction of the particles cluster.