Flow field uniform distribution device suitable for adjustable shrinkage cavity of pulverized coal pipeline

The invention discloses a flow field uniform distribution device suitable for an adjustable shrinkage cavity of a pulverized coal pipeline, which comprises a shell, a central bluff body arranged at the center of the shell, and a first flow guide ring, a second flow guide ring and a third flow guide ring arranged between the shell and the central bluff body from outside to inside. The first flow guide ring, the second flow guide ring and the third flow guide ring are connected with the shell through the supporting ribs. The central bluff body comprises a lip-shaped bluff body and annular blades arranged in the circumferential direction of the lip-shaped bluff body, and an air inlet and an air outlet are formed in the shell in the axial direction. And a multi-layer annular airflow channel is formed among the first flow guide ring, the second flow guide ring, the third flow guide ring, the central bluff body and the shell. The distribution characteristic of airflow after adjustable shrinkage of the primary air p