Abstract: The five-hole probe was used to investigate three-dimensional gas flow field in a new cyclone-granular bed coupling separation equipment. The results show that the distribution of dimensionless tangential velocity is similar to that of configurations axial velocity under different inlet gas velocities; the axial symmetry of tangential velocity distribution is good, and the center of swirl is coincident with the center of geometry; the tangential velocity is decreased along the axial direction, but the radial distribution is different from that of the conventional cyclone; in the entrance annular space, the tangential velocity is increased in the range of 0°- 180°, but is decreased in the range of 180°- 270°; in the swirl space, the local spiraling air is concentrated at the 270° direction of the cylinder-cone connection; the law of radial velocity distribution is not obvious, and the radial velocity is the same order as the axial velocity in the straight tube section and has an important influence on the direction of the air flow; at the inlet section of exhaust pipe, the direction of external swirl flow is closely related to the inlet gas velocity. Combined with the distribution of the dynamic pressure field, it can be concluded that the gas flow in the cylinder-cone connection section is obviously decreased, and some gas is spiraled up into the granular bed, which may lead to the accumulation of dust in the actual operation. Due to the influence of the built-in particle bed, the whole gas phase inside the device moves in a spiral downward swirl flow, and the inner and outer boundary of the swirl flow is not very obvious. Because of the phenomena of short-circuit flow, the top ash ring and the back mixing are disappeared at the outlet of exhaust pipe.

Key words: cyclone, granular bed, coupling, gas flow field, distribution