Two-Dimensional Parallel Computing Solution of Coupled Heat and Moisture Flow in Unsaturated Soil

Abstract

A two-dimensional parallel algorithm for coupled heat and moisture transfer in unsaturated soil is presented. A theoretical formulation, which was recently published in the literature is adopted for the work. The algorithm, based on a numerical finite difference explicit solution scheme, is programmed in the concurrent language Occam and executed on a parallel computing network of transputers. An assessment of the two-dimensional algorithm in terms of its overall computational performance is also performed, together with an investigation of its accuracy. The ability of the numerical algorithm to fully model the complex, interrelated, coupled nature of the two-dimensional transient and steady-state phenomenon was demonstrated, including the gravitational effects. The computational efficiency of the approach was found to be very high. Further, a superior computational performance was achieved when applying the two-dimensional approach to a larger network of processors as well as to a larger size of problem. The accuracy of the model was also established by comparison of results with values produced by an alternative, completely independent numerical approach. Excellent correlation was obtained.