Fast Calculating Method and In-Mold Labeling Model for Cooling Analysis in Injection Molding

Abstract

Cooling analysis with the boundary element method (BEM) forms full-matrix equations in injection molding. Computers have no ability to handle it when the element number is more than its acceptance. This paper adopts the elements incorporation method. It changes the original model from one large matrix equation to one small union matrix equation and several small block matrix equations. In this way, the calculation time is shortened considerably and the treatable number of element in cooling analysis is enhanced dramatically. In-mold labeling processing, which adds a label on part surface in the mold is a new technology, and it is becoming more and more popular. It affords the mold designer far greater latitude in the design of graphics, part shape, and the use of multiple molded components in a single molded unit. Its simulation is a new task in computer aided engineering (CAE). This paper is based on the feature that the cavity surface is always meshed into planar triangular elements, Supposing that the label and part are two plates with perfect contact, establishes a one dimensional unsteady heat transfer model under the first dissymmetry boundary for each element. Using this heat transfer model, the cooling analysis model of in-mold labeling is established.

Keywords:

• Boundary element method (BEM)
• Cooling analysis
• Injection molding
• In-mold labeling
• Linear equations
• Numeric algorithms