Flow and transport simulations using T2CG1, a package of conjugate gradient solvers for the TOUGH2 family of codes Page: 6 of 131
This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
ABSTRACT
T2CG1, a package of preconditioned conjugate gradient solvers, has been added to
the TOUGH2 family of codes to complement its direct solver (MA28) and significantly
increase the size of tractable problems(*). T2CG1 is 'plug-compatible' with the 1991
Version 1.0 of TOUGH2, and retains the option of using the direct solver MA28. T2CG1
includes three new solvers: a Bi-Conjugate Gradient (BCG) solver, a Conjugate Gradient
Squared (CGS) solver, and a Generalized Minimum Residual (GMRES) solver. T2CG1 is
tested in the solution of 16 non-linear test problems ranging from one-dimensional single-
phase isothermal flow to complex three-dimensional three-phase multicomponent non-
isothermal flow and transport with phase changes. Results from a variety of computing
platforms and from systems with up to 30,000 equations show that the CG routines in
T2CG1 (1) demonstrate a problem-, compiler-, and machine-specific performance, as is the
case for all iterative solvers, (2) are significantly (and invariably) faster than MA28, and (3)
require far less memory than the MA28 direct solver, and thus (4) enable the solution of
much larger problems (previously tractable on supercomputers only) on microcomputers.
The DSLUCS solver has the best overall performance.
The present series of tests includes multiphase, multicomponent fluid and heat flow
problems related to geothermal reservoirs, vadose zone hydrology, nuclear waste disposal,
and environmental remediation. Although one or two solvers performed poorly in certain
problems, each of the 16 test problems could be efficiently and accurately solved by at least
one of the T2CG1 routines.
The T2CGl module is available from: Energy Science and Technology Software Center (ESTSC), P.O.
Box 1020, Oak Ridge, TN 37831; telephone: (615) 576 2606; e-mail: estsc@adonis.osti.gov.iii
Upcoming Pages
Here’s what’s next.
Search Inside
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Moridis, G. & Pruess, K. Flow and transport simulations using T2CG1, a package of conjugate gradient solvers for the TOUGH2 family of codes, report, April 1, 1995; California. (https://digital.library.unt.edu/ark:/67531/metadc624956/m1/6/: accessed April 19, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.