NUMERICAL MODELING OF VOID MIGRATION IN SOLIDS DUE TO TEMPERATURE-GRADIENT USING THE BOUNDARY-ELEMENT METHOD

Voids (a kind of flaw) are not desired in the products of many industr ial and manufacturing processes. In this article, we seek effective wa ys to remove the void by modeling the void migration and predicting th e intermediate and the final shape of the cavity. The boundary element method (BEM) is applied to the quasi-steady state void migration proc ess governed by Laplace's equation. The conduction solution depends on the void shape, and the void shape depends on the conduction solution . Hence this is a conjugate problem. The analytical formulation and th e numerical approach are outlined. The Overhauser spline elements are used in the BEM to ensure continuous first-order derivatives on the vo id boundary. Given the material properties, geometry of the physical m odel and boundary conditions, this computer model can predict detailed information such as flux, velocity and direction of void motion, and temperature at any stage of the void migration. Different strategies f or void removal are investigated.