A rapid BEM-based method for cooling simulation of injection molding

Abstract

Cooling simulation is significant for optimization of the cooling system of injection molds. The boundary element method (BEM) is thought to be one of the best approaches suiting the steady-state cooling simulation. In spite of the merits of the BEM, the long computational time and the exorbitant memory requirement are two bottleneck problems in the current BEM-based cooling simulation method for industrial applications. The problems are caused by two reasons. One is the coupled heat transfer between the mold and the part and another is attributed to the inherent drawback of the BEM. In this article, the outer iteration, which is traditionally used to achieve consistency of boundary conditions on the mold cavity surface, is eliminated by introducing analytical solutions of the part temperature into the BEM equations. Then the dense coefficient matrix is sparsified by a combination of coefficient items using geometric topology. Moreover, parallel computing has been employed to speed up the computation. The case study showed that the sparse ratio reaches 7% with a temperature error of ±1 oC and the total computational time is reduced by almost one order of magnitude simultaneously.