Abstract: This paper systematically analyzes the cyclone gas flow field in the separating column of a circumfluent circulation cyclone separator based on the Navier-Stokese equation and the continuity equation of ideal flow under columnar coordinates. The Adomian decomposition-inverse operator method was used to solve the flow field. The basic representations of radial velocity, tangential velocity and axial velocity of the ideal flow in the separating column were derived, and computation values were compared with experimental values The mathematical model and computation equations were proved to be reasonable.