|
|
|
Enhancing the Pyramid Parallel Unstructured Adaptive Mesh Refinement Library
|
|
|
| The objective of this proposal is to introduce significant and relevant enhancements to the PYRAMID parallel unstructured adaptive mesh refinement library. Developed under the ESTO Computational Technologies Program, this freely available tool is currently used for large-scale mesh generation and solution adaptive mesh refinement for Earth and space science applications. More than 100 downloads of the current version of the tool exist, but there is growing interest in the research, commercial and private sector for additional functionallity to be incorporated into the tool. This proposal will add such features including improved memory usage, support for commercial mesh generator formats such as NASTRAN, IDEAS, Solidworks, and Unigraphics, full implementation of the C interface, a web tutorial for on-line training, additional improvements to mesh coarsening routines, retrofitting of 3D features to the 2D version, and parallel I/O support. AISR has supported similar activities for other AMR too development in the past so this proposal is relevant to the goals of the program.
The work will be accomplished by redesigning aspects of the central data structure to more effectively handle memory usage while providing support for unstructured adaptive mesh coarsening (based on techniques of R. Lohner) with quality control. (Quality control prevents creation of elements with poor geometry as the mesh structure changes.) Translators will be generated to support the commercial mesh generation formats, routines will be added to the C-interface library since PYRAMID is written in Fortran 95, and large-scale I/O will be managed using either HDF-5 and/or aspects of MPI-IO. No new numerical techniques need to be added to the library.
This work is significant to the objectives of the solicitation as it is cross-cutting and bridges NASA SMD interests in Earth and Space science. One of the major challenges facing these communities involves modeling and interpretation of data from observational measurements. As missions are planned, and as results are obtained, achieving analysis goals will depend on coupling physics-based solvers with advanced mesh/grid infrastructure tools for parallel computers, such as Project Columbia and others. This ranges from understand Earthquake science to modeling of space physics phenomena. We have, for example, used this tool as part of the Quakesim project that models surface deformation for active tectonics and other Solid Earth processes. Such a capability is directly relevant to the development of an InSAR analysis system as large-scale adaptive grids, when coupled with geophysics solvers, can assimilate InSAR measurements to model deformation processes. It has also been used for magnetosphere flow modeling as part of Earth-Sun system simulation models as well as problems in structural mechanics engineering.
This proposal responds to the following NASA strategic objective: Conduct a program of research and technology development to advance Earth observation from space, improve scientific understanding, and demonstrate new technologies with the potential to improve future operational systems. |
|
|
