A computationally efficient solution technique for moving-boundary problems in finite media

A new technique is developed for plane or spherical moving-boundary problems, such as occur in freezing or melting problems. A coordinate transformation for immobilization of the moving boundary is used. The technique involves the use of a semidiscrete Petrov-Galerkin method with the piecewise-exponential test functions and the piecewise-linear trial functions to approximate the time-dependent governing equation and the use of a predictor-corrector method to integrate the boundary motion equation. Computed results for the plane or spherical moving boundary are numerically evaluated for comparison with results of previous authors. This method is simple and there is no limit on the range of the parameters. We argue that the method is well-suited to a variety of moving-boundary problems.