The computer simulation to the function of the screw with a pin mixing section

Theoretical study of the mixing of fluid due to pins is presented by analyzing the movement and distortion of the fluid around the pins. This paper used a computer to simulate the condition of fluid flow around the pins and calculated the velocity and pressure distribution in the flow field by The Finite Element Method when the diameter, space, shape, arranged manner of pins and rotation velocity of the screw changed. According to the calculated result, the weighted average total strain has been chosen as a mixing index to evaluate mixing effectiveness for each condition. The result shows that under the actions of pins viscous fluid produced both shearing and tensile distortion. It is for the existence of the two distortions the mixing is intensified. The diameter, space, shape, arranged manner of pins and rotation velocity of the screw all have obvious functions to the mixing.