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In order to perfect the theory on the cyclical slit flow of concentricity, the distribution features of the cyclical slit flow were analyzed from stopping to starting and to run procedure on the cylinder by a combination of theoretical analysis and model experiments. It is concluded that the speeds of the cylinders, the gap widths and the discharges have effect on the distribution and magnitude of the cyclical slit flow. The cyclical slit flow velocity increased firstly and then decreased as the gap width enlarged. When the gap width was about 2cm, the cyclical slit flow velocity reached a maximum. The larger the discharge was, the larger the cyclical slit flow velocity would be. The larger the speed of the cylinder was, the larger the cyclical slit flow velocity would be. The cyclical slit flow rate increased to the maximum before the speed of the cylinder, the cyclical slit flow rate and the water velocity in the pipe intersect decreased to the minimum after that. Meanwhile mathematical model of the cyclical slit flow of concentricity under the moving boundary condition was established. The calculated values and experimental values are in substantial agreement and maximum relative error is no more than 8.5%, which showed the mathematical model is rational.