A point implicit time integration technique for slow transient flow problems

Samet Y. Kadioglu, Ray A. Berry*, Richard C. Martineau

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

Abstract

We introduce a point implicit time integration technique for slow transient flow problems. The method treats the solution variables of interest (that can be located at cell centers, cell edges, or cell nodes) implicitly and the rest of the information related to same or other variables are handled explicitly. The method does not require implicit iteration; instead it time advances the solutions in a similar spirit to explicit methods, except it involves a few additional function(s) evaluation steps. Moreover, the method is unconditionally stable, as a fully implicit method would be. This new approach exhibits the simplicity of implementation of explicit methods and the stability of implicit methods. It is specifically designed for slow transient flow problems of long duration wherein one would like to perform time integrations with very large time steps. Because the method can be time inaccurate for fast transient problems, particularly with larger time steps, an appropriate solution strategy for a problem that evolves from a fast to a slow transient would be to integrate the fast transient with an explicit or semi-implicit technique and then switch to this point implicit method as soon as the time variation slows sufficiently. We have solved several test problems that result from scalar or systems of flow equations. Our findings indicate the new method can integrate slow transient problems very efficiently; and its implementation is very robust.

Original languageEnglish
Pages (from-to)130-138
Number of pages9
JournalNuclear Engineering and Design
Volume286
DOIs
Publication statusPublished - May 2015
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.

Funding

The submitted manuscript has been authored by a contractor of the U.S. Government under Contract No. DEAC07-05ID14517. Accordingly, the U.S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U.S. Government purposes.

FundersFunder number
U.S. GovernmentDEAC07-05ID14517

    Fingerprint

    Dive into the research topics of 'A point implicit time integration technique for slow transient flow problems'. Together they form a unique fingerprint.

    Cite this