DOE ACTS COLLECTION Workshop Robust and High Performance Tools for Scientific Computing September 4-7, 2002

Efficient solution of large-scale problems arising from discretization of multiphysics couplings of models with multiple scales in field-scale subsurface modeling. In particular, model-based MIMD local balancing and nonlinear solvers.

In recent years it has been recognized that the simulation of subsurface flow and transport must be accompanied by simulation of all the coupled phenomena that influence, or are influenced by, these phenomena at all relevant scales. However, in spite of the emergence of new computational methodologies and the dramatic increases in computational power, for many reasons it is still difficult or impractical to formulate large comprehensive models which would account for all of the coupled phenomena in one model or in one code especially if there is need to account for multiple spatial and temporal scales. As an alternative to comprehensive models, one sees the emergence of multiphysics couplings.

In the geosciences various applications have relied on multiphysics couplings which connect models or algorithms in adjacent or in overlapping computational domains. Models can be coupled in a loose (staggered-in-time) fashion or more tightly, where a solution is obtained by iterating between models. In addition, multiple models can be defined in overlapping domains; data exchange is handled by interpolation/projection algorithms. Challenges include parallel scaling and launching of different components on different remote platforms as well as handling huge amounts (terabytes) of input/output data which needs to be post-processed.

1. Qin Lu, Malgorzata Peszynska, Mary F. Wheeler, A Parallel Multi-Block Black-Oil Model in Multi-Model Implementation, SPE 66359, Proceedings of SPE Reservoir Simulation Symposium, Houston, TX, Feb. 11-14, 2001, also: SPE Journal, to appear.

2. Mary F. Wheeler, John A. Wheeler, and Malgorzata Peszynska, A Distributed Computing Portal for Coupling Multi-Physics and Multiple Domains in Porous Media, XIII International Conference on Computational Methods in Water Resources, Calgary, Alberta, Canada, Bentley, L.R. and Sykes, J.F. and Brebbia, C.A. and Gray, W.G. and Pinder, G.F., eds., p. 167-174, Balkema, 2000

3. Malgorzata Peszynska, Mary F. Wheeler, Ivan Yotov, Mortar upscaling for multiphase flow in porous media, Computational Geosciences 6 (2002)