205 プラスチック成形加工における最適化解析

抄録

This study focuses up on the optimization analysis of the blow molding and the extrusion molding in the polymer processing. In order to predict the optimal thickness distribution of the preform, the membrane FEM (Finite Element Method) iterative calculations were applied to simulate the blow molding process utilized in the manufacture of the PET bottle. In these iterative calculations, we employed an optimization method based on TEM (Trial and Error Method). This method properly modifies the initial thickness properties of the membrane elements to diminish the difference between the predicted thickness and the optimal value. As a result, the optimal initial condition of the preform to produce the PET bottle with the uniform thickness can be predicted within practical computation time. In addition, we applied the solid FEM simulations to uniform the flow rate in the branched channel used in the extrusion molding. The Thompson's transformation-remeshing rule was employed to modify the FEM meshes. The hybrid optimization method based on TEM and RSM (Response Surface method) including GA (Generic Algorithm) were introduced to reduce the number of times for a try and error calculation in DOE (Design Of Experiment). These optimization analyses provide rational means to assist the mold design and the determination of the optimal process conditions in the polymer processing.