摘要：The unsteady anisotropic Helmholtz type equationof spatially varying coefficients is considered in this study.The study is to find numerical solutions to initial boundaryvalue problems governed by the equation. Such problemsare relevant for anisotropic functionally graded materials.A mathematical analysis is used to transform the variablecoefficient equation to a constant coefficient equation whichis then Laplace-transformed (LT) to get a time-independentequation. The latest equation is then written as a boundaryonly integral equation of a time-free fundamental solution. Aboundary element method (BEM) which is derived from theintegral equation and combined with the Stehfest formula fornumerical Laplace transform inversion is then employed to findthe numerical solutions. Some problems are considered. Thecombined LT-BEM is easy to implement. The results show thatthe numerical solutions obtained are accurate.
