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LANS Publications

"Geophysical-Astrophysical Spectral-Element Adaptive Refinement (GASpAR): Object-oriented h-adaptive code for geophysical fluid dynamics simulation"

D. Rosenberg, A. Fournier, P. Fischer, and N. Pouquet

. Also Preprint ANL/MCS-P1245-0405

Preprint Version: [pdf]

We present an object-oriented geophysical and astrophysical spectral-element adaptive refinement (GASpAR) code for application to turbulent flows. Like most spectral-element codes, GASpAR combines finite-element efficiency with spectral-method accuracy. It is also designed to be flexible enough for a range of geophysics and astrophysics applications where turbulence or other complex multiscale problems arise. For extensibility and flexibility the code is designed in an object-oriented manner. The computational core is based on spectral-element operators, which are represented as objects. The formalism accommodates both conforming and non-conforming elements and their associated data structures for handling interelement communications in a parallel environment. Many aspects of this code are a synthesis of existing methods; however, we focus on a new formulation of dynamic adaptive refinement (DARe) of nonconforming h-type. This paper presents the code and its algorithms, we do not consider parallel efficiency metrics or performance. As a demonstration of the code we offer several two-dimensional test cases that we propose as standard test problems for comparable DARe codes. The suitability of these test problems for turbulent flow simulation is considered.