Study on the mixing performance of one differential twin-screw kneader

Abstract

Twin-screw kneader is an efficient polymer processing equipment. The mixing performance is a very important index for the twin-screw kneader. In this paper, the mixing performance of one novel intermeshing counter-rotating twin-screw kneader with different tip angles of the male rotor was simulated using the mesh superimposition technique (MST). Statistical analysis was carried out for the flow field using particle tracking technique, and distributive mixing performance is evaluated using the residence time distribution and segregation scale, while the dispersive mixing performance is estimated using the average of the maximum shear rate and stretching rate as well as the mixing index. The results show that the best distributive mixing performance is achieved when the tip angle is 0°, while the optimal dispersive mixing performance is obtained when the tip angle is 20°. One experimental apparatus of the twin-screw kneader is built up to perform the mixing performance using three color masterbatch materials with the screw rotors. The results in this paper provide a data basis for the selection of parameters and optimization of the mixing performance for the differential twin-screw kneader.

Keywords

• tip angle
• twin-screw kneader
• rotor profiles
• distributive mixing performance
• dispersive mixing performance