二軸スクリュ押出機の性能に関する理論的研究第1報三次元流動解析のためのコンピューターシミュレーション手法の開発とそれを用いた各種洩漏流の評価
Theoretical Study on Performance of a Twin Screw ExtruderI. Development of a Computer Simulation Method for Three Dimensional Flow Analysis and Evaluation of Various Leakage Flow Using This Method
梶原稔尚・中野祥生・二之宮慎一・船津和守
Kajiwara, Toshihisa / Nakano, Yoshio / Ninomiya, Shinichi / Funatsu, Kazumori
We have developed a three-dimensional analysis technique for non-Newtonian flow in a melt conveying zone of a counter-rotating intermeshing twin screw extruder by the finite element method. We used a reference frame moving with the apparent velocity of the screw flight because the analysis zone changes with time for the stationary reference frame. As a result, the complex transport mechanism in the twin screw extruder could be understood from the obtained velocity fields. We evaluated the flow rate for various kinds of leakage flow for varying screw geometries. It was found that the flow rate of interchanged fluid which transferred from one screw to the other became larger with increasing side gap and with decreasing calender gap. We also calculated the maximum shear stress distribution which was an important characteristic of the mixing performance. Furthermore, we estimated the temperature rise by viscous heat generation which is related to the thermal degradation of the polymers.
Key words: Twin screw extruder / Three dimensional flow analysis / Non-Newtonian flow / Finite element method