Efficient Explicit-Implicit Finite Difference Algorithm for Transient Heat Conduction Problems

An efficient explicit-implicit finite difference algorithm for the transient heat conduction problem is developed. The algorithm is based on the alternative use of the explicit and implicit scheme for the time integral of the transient heat conduction equation depending on the total heat conductance of mesh elements. The algorithm has so simple a structure that it can be applicable to a variety of transient heat conduction problems. Particularly, the algorithm is effective for multi domain problems and strongly irregular mesh problems. In this paper, the basic idea of the algorithm and a method to determine an optimum time increment are described. Also, the evaluated results of accuracy and acceleration of the calculation by the application to the one-dimensional transient heat conduction problems are described.