An OpenVSP model may be exported in a wide variety of formats including triangulated meshes, rectilinear wireframes, standardized CAD, vector drawings, blade element, and airfoils, among others. Each of these file types will require their own options and model setup to achieve a quality export which will be discussed in subsequent topics along with reasonable best-practices. The Export menu is located in the File menu. Similar to Comp Geom, users may select different components for the Normal (thick-surface) set and the Degen (thin, camber surface) set.
Blade element momentum (BEM) models may be imported to OpenVSP as Prop components in which each of the BEM stations are set as Prop blade control points. Because the Prop component is perhaps the most complex geometry in OpenVSP, it can take quite a while to update models with excessive numbers of control points when in Blades mode. This tends to happen when imported BEM models can have 20+ stations. A way to alleviate this is to switch the Prop to Disk mode, which doesn’t require a visual update to loft the blade with each parameter change. Users may also wish to convert the blade control curves to Approximate Cubic Bezier to reduce the number of points. This can be quickly accomplished for all blade curves by clicking “Approximate All” under the Blade tab.
For more information about working with Prop components, refer to the Propellers subject and topics.
Point clouds may be imported into an OpenVSP model from the Import… menu. The point cloud (PTS) format is a very simple X Y Z triad with each row corresponding to a new point, which makes these files very easy to read and write. Once imported, the point cloud may be used as a visual target for manual modeling or as Fit Model targets.
Heritage OpenVSP v2 models may be imported from the Import… menu. In most cases, the translation from OpenVSP v2 components to their OpenVSP 3 counterparts is very straightforward and has been automated as much as possible. For example, version 2 parameters defining a Wing will be directly applied to the matching parameters in version 3. A similar process occurs for fuselages cross-sections and skinning parameters. However, some VSP2 parameters or methods do not exist in VSP3 models or components and may require some manual iteration to match the design exactly. In such cases, it is recommended that the VSP2 model is imported along with a mesh from OpenVSP v2 to provide a guide for any required corrections.
Wireframes of Hermite (HRM) or Plot3D (P3D) format may be imported to OpenVSP models from the Import… menu. Hermite files have the option of importing as triangulated meshes or as wireframes. Note that some Hermite components may import with the reflected surface normals inverted which will be easily identified by shading the surface, resulting in a dark or shadowed effect.