Japan Geoscience Union Meeting 2015

Presentation information

Print

Oral

Symbol P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM26] Space Plasma Physics: Theory and Simulation

Sun. May 24, 2015 2:15 PM - 4:00 PM 302 (3F)

Convener:*Takayuki Umeda(Solar-Terrestrial Environment Laboratory, Nagoya University), Takanobu Amano(Department of Earth and Planetary Science, University of Tokyo), Yasuhiro Nariyuki(Faculty of Human Development, University of Toyama), Tooru Sugiyama(Japan Agency for Marine-Earth Science and Technology Center for Earth Information Science and Technology), Tadas Nakamura(Fukui Prefectural University), Chair:Yasuhiro Nariyuki(Faculty of Human Development, University of Toyama), Takayuki Umeda(Solar-Terrestrial Environment Laboratory, Nagoya University)

3:15 PM - 3:30 PM

[PEM26-19] Yin-Yang-Zhong: An overset grid for a sphere

*Akira KAGEYAMA1 (1.Graduate School of System Informatics, Kobe University)

Keywords:Yin-Yang grid, overset grid, computer simulation, Yin-Yang-Zhong grid

Computation in a spherical region bounded by a constant radius is important in various fields of science and technology. Spatial discretization inside a sphere is not simple because there is no orthogonal coordinate system that fits to a sphere, without a coordinate singularity. The spherical polar coordinate system, for example, has two kinds of coordinate singularity; one on the poles and another on the origin. Singularity should be avoided in numerical simulations because it causes grid convergence around the singular point. We have developed a new grid system for a sphere, Yin-Yang-Zhong grid, which is an overset grid system composed of Yin-Yang grid and Zhong grid. Yin-Yang grid itself is an overset grid system that covers the outer spherical shell part inside the sphere. Zhong grid is a Cartesian grid-base system to cover the central part of the sphere. We have developed a magnetohydrodynamic simulation code for a sphere based on the Yin-Yang-Zhong grid. The code is parallelized with MPI. We have performed a quantitative tests of the code with diffusion and advection problems.