Justification of Design and Technological Parameters for Air-Screw Separator

Abstract

The article presents the model of the air flow moving and pressure occurring in the screw aspiration channel of the air-screw separator created with ANSYS CFX program as a highly efficient means for computational fluid dynamics to describe gas motions with Navier-Stokes differential equations. The air flow rate in the screw aspiration channel is found to increase as the pressure decreases thrice due to changes in the cross-sectional area when the air enters the transition piece with the initial rate of 3.5 m/s. Thus, the mathematical dependence of the air flow pressure on the length of the separator working element is obtained: if the length is 1.5 m, the pressure of the air fan is 385 Pa, the initial air flow rate is 3 m/s when the transition piece is used, and 7.5 m/s in the screw aspiration channel. The article substantiates the main design and technological parameters of the air-screw separator working element: the diameter is to be 0.3 m, the length is to be 0.75 m, the length of the cleaning screw element is to be 0.7 m, and the cross-sectional area of the aspiration channel is to be 0.33 m2. The rational screw rotation speed is found to be 60 rpm.