MHD dynamo simulation using the GeoFEM platform—verification by the dynamo benchmark test

Abstract

We verified a magnetohydrodynamic (MHD) simulation code in a rotating spherical shell using the parallel finite element method by comparing with the dynamo benchmark test by Christensen et al. [“A numerical dynamo benchmark”, Physics of Earth and Planetary Interiors, 128 (2001), 25–34]. We performed the non-magnetic case and dynamo with the insulated inner core case of the benchmark test. The results show that all results of the MHD case have <5% differences from the benchmark solutions. Only the drift frequency in the non-magnetic case duffers by more. This discrepancy is attributed to the small amplitude of the drift frequency in the non-magnetic case. We conclude that the present simulation code can represent dynamics and behavior of convection pattern and magnetic field although the present simulation model has some limitations such as the finite size of simulation domain.

Keywords:

• Geodynamo
• Magnetohydrodynamics
• Finite element method
• Dynamo benchmark test

Acknowledgements

This study is part of the “Solid Earth Platform for Large-Scale Computation” project funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan, through the Special Promoting Funds of Science & Technology. The authors would like to thank Dr Masaki Matsushima and Dr Futoshi Takahashi for comparing with their benchmark results, Dr Yoshitaka Wada for his work on mesh generation, our colleagues in the GeoFEM project team for their support, the Earth Simulator center and the National institute for Poler Research for performing the present simulations.

Notes

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Additional information

Notes on contributors

Hiroshi Okuda

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