Open-Source Software

Downloads

macOS

dmg image for macOS 10.11 or later; 64bit processor required. Most development is performed on macOS, hence this is the best-supported version.

Linux

Standalone package from which sumo and scope can be run without rpm/yum/apt installation.

Windows

7z archive - unpack and run from the directly folder; no installation needed.

The complete source code is also available for download, including most third-party open-source packages which are needed to compile. Please note that this package is updated every day. Some of the libraries are under active development, and thus there is no guarantee that every nightly package update will work perfectly (or even compile).

Modeling and Mesh Generation

The surface modeler sumo is a graphical tool aimed at rapid creation of aircraft geometries and automatic surface mesh generation. sumo is not a full-fledged CAD system, but rather a easy-to-use sketchpad, highly specialized towards aircraft configurations.

Modeling

The surface modeler is based on a C++ library for geometric primitives such as b-spline surfaces,and currently provides a graphical frontend to a small subset of the library. Sumo is actively developed in order to streamline the workflow as far as possible to the intended use: Rapid surface modeling of aircraft configurations.

Mesh Generation

Mesh generation in sumo Unstructured surface meshes can be generated completely without user intervention. Heuristics determine default parameters for the mesh generation code, which usually yield a satisfactory mesh. Manual tuning of these parameters is possible as well.

Triangulations are based on a three-dimensional in-sphere criterion, which yields better mesh quality than Delaunay methods for strongly skewed surfaces, such as thin, swept delta-wings. Geometric refinement criteria produce a finer mesh in regions of strong curvature, while a limit on the minimum element size can be imposed to avoid resolution of irrelevant geometric detail. Unstructured volume meshes can be generated from the surface mesh, provided that Hang Si's tetrahedral mesh generator TetGen is available. The volume mesh can be saved as CGNS, a bmsh file for the CFD solver EDGE, or TetGen's plain ascii format.

Postprocessing

Volume mesh cut Scope is a visualization program to display results generated by the dwfs potential flow solver. Furthermore, it can read many NASTRAN bulk data files as well as modal analysis results and animate modeshapes. Finally, scope animates time-domain flight trajectories of rigid as well as elastic aircraft.

Features

Originally, scope was a graphical postprocessing tool for the potential flow solver dwfs . It currently displays meshes and scalar surface data such as potential, source and pressure distributions in the form of three-dimensional color-coded surface plots. Point results can be extracted by simply clicking on a mesh node.

To support the work of the aeroelastician, scope can also display NASTRAN meshes and results. However, it is not meant to be a generic NASTRAN postprocessor; some valid NASTRAN formats are not supported yet, and not all element types can be rendered.

Documentation

A commercial user funded the writing of a user manual for the graphical postprocessing tool scope. This manual is packaged with the application (in the folder userdoc) and also available online. The modeling and mesh generation software sumo does not have a user manual yet.

Future Developments

At the time of writing, active development of the open-source tools is limited to bug fixes and small feature additions. Should you need additional features or documentation, these can often be provided at very reasonable terms.

If you are interested in using or modifying sumo or scope yourself, either for academic or commercial applications, you are certainly free to do so under the terms of the GPL. Also I'm interested to hear from you in order to be aware of possible interest, there is no need to ask for permission.