It solves a set of coupled mass and energy balance equations using a finite volume method. The parallel implementation first partitions the unstructured computational domain. For each time step, a set of coupled non-linear equations is solved with Newton iteration.
Communication is required for convergence tests and data exchange across partitioning borders.
Parallel performance results on Cray T3E-900 are presented for two real application problems arising in the Yucca Mountain nuclear waste site study. The execution time is reduced from 7504 seconds on two processors to 126 seconds on 128 processors for a 2D problem involving 52,752 equations. For a larger 3D problem with 293,928 equations the time decreases from 10055 seconds on 16 processors to 329 seconds on 512 processors.