Abstract: The numerical simulation has been carried out to investigate the effect of the bluff-body with different structural parameters on the cold flow characteristics in advanced vortex combustor (AVC). The results show that cavity has stable flow characteristics when B₂/B₁=0.7, L/B₁=0.8, and the total pressure loss is the least. The effect of incoming velocity on flow characteristics was studied with the optimal structural parameters. The results show that the total pressure loss increases with the increase of incoming velocity. The variation amplitude of the total pressure loss is far greater than that of incoming velocity. The cavity of AVC can stabilize the flame under the high incoming velocities.