Polymer cross flow in the screw-based plasticating system
Polimery 2001, No 3, 184
In reference to the comparison of polymer flow velocity along the helical channel in the screw-based plasticating system in dependence on kinematical model used, which was presented in previous publications  and , further comparative studies on these models for cross flow we re executed. Studies were carried out in rectangular and helical coordinate systems for both previously compared models that is for the model with rotating barrel and the model with rotating screw (Fig. 1-4). It has been stated that polymer cross flow velocity and its distribution are different in both models and both coordinate systems (Fig. 5-10). Drag cross flow velocity (the barrel rotates) is higher than redrag polymer flow velocity (the screw rotates) which is caused by different barrel and screw peripheral speeds. In rectangular and helical coordinate systems the highest values of drag (redrag) flow velocities are the same for helical channels of different depths. The distributions of both drag and redrag flow velocities computed in rectangular coordinate system are different than computed in helical coordinate system. The distribution of pressure cross flow velocity computed in rectangular system is different than in helical coordinate system.
Keywords: plasticating systems, polymer flows, kinematical model with rotating barrel, kinematical model with rotating screw, rectangular and helical coordinate systems