Many important problems in astrophysics, space physics, and geophysics involve flows of (possibly ionized) gases in the vicinity of a spherical object, such as a star or planet. The geometry of such a system naturally favors numerical schemes based on a spherical mesh. Despite its orthogonality property, the polar (latitude-longitude) mesh is ill suited for computation because of the singularity on the polar axis, leading to a highly non-uniform distribution of zone sizes. The consequences are (a) loss of accuracy due to large variations in zone aspect ratios, and (b) poor computational efficiency from a severe limitations on the time stepping. Geodesic meshes, based on a central projection using a Platonic solid as a template, solve the anisotropy problem, but increase the complexity of the resulting computer code. We describe a new finite volume implementation of Euler and MHD systems of equations on a triangular geodesic mesh (TGM) that is accurate up to fourth order in space and time and conserves the divergence of magnetic field to machine precision. The paper discusses in detail the generation of a TGM, the domain decomposition techniques, three-dimensional conservative reconstruction, and time stepping.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7144351PMC
http://dx.doi.org/10.1186/s40668-020-00033-7DOI Listing

Publication Analysis

Top Keywords

geodesic mesh
8
astrophysics space
8
time stepping
8
technologies supporting
4
supporting high-order
4
high-order geodesic
4
mesh
4
mesh frameworks
4
frameworks computational
4
computational astrophysics
4

Similar Publications

With the advancement of service robot technology, the demand for higher boundary precision in indoor semantic segmentation has increased. Traditional methods of extracting Euclidean features using point cloud and voxel data often neglect geodesic information, reducing boundary accuracy for adjacent objects and consuming significant computational resources. This study proposes a novel network, the Euclidean-geodesic network (EGNet), which uses point cloud-voxel-mesh data to characterize detail, contour, and geodesic features, respectively.

View Article and Find Full Text PDF

Maxillofacial bone movements-aware dual graph convolution approach for postoperative facial appearance prediction.

Med Image Anal

January 2025

Department of Oral Craniomaxillofacial, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China; College of Stomatology, Shanghai Jiao Tong University, Shanghai 200125, China; National Center for Stomatology, Shanghai 200011, China; National Clinical Medical Research Center for Oral Diseases, Shanghai 200011, China; Shanghai Key Laboratory of Stomatology, Shanghai 200011, China; Shanghai Research Institute of Stomatology, Shanghai 200011, China; Research Unit of Oral and Maxillofacial Regenerative Medicine, Chinese Academy of Medical Science, Shanghai 200011, China. Electronic address:

Postoperative facial appearance prediction is vital for surgeons to make orthognathic surgical plans and communicate with patients. Conventional biomechanical prediction methods require heavy computations and time-consuming manual operations which hamper their clinical practice. Deep learning based methods have shown the potential to improve computational efficiency and achieve comparable accuracy.

View Article and Find Full Text PDF

Fast detection of exact point-to-point geodesic paths on meshes is still challenging with existing methods. For this, we present a method to reduce the region to be investigated on the mesh for efficiency. It is by our observation that a mesh and its simplified one are very alike so that the geodesic path between two defined points on the mesh and the geodesic path between their corresponding two points on the simplified mesh are very near to each other in the 3D Euclidean space.

View Article and Find Full Text PDF

Constructions of innovative geodesic domes in terms of the sustainable and efficient cross-sections using.

Sci Rep

September 2024

Faculty of Civil Engineering and Architecture, Opole University of Technology, Katowicka 48, 45-758, Opole, Poland.

Geodesic domes are structures which deliver effective solutions, associated with cost savings, due to the lack of intermediate supports when roofing large-sized objects. The multitude of advantages of this type of construction was translated into the shaping of innovative lightweight objects of geodesic domes, constructed on a regular octahedron. In this article, the use of strut sections was applied to covers generated due to a regular octahedron.

View Article and Find Full Text PDF

Many 3D mesh processing tasks revolve around generating and manipulating curves on surface meshes. While it is intuitive to explicitly model these curves using mesh edges or parametric curves in the ambient space, these methods often suffer from numerical instability or inaccuracy due to the projection operation. Another natural strategy is to adapt spline based tools, these methods are quite fast but are hard to be extended to more versatile constraints and need heavy manual interactions.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!