Shrinkwrapping is a powerful tool that enables users to create a meshable geometry from CAD and STL models that may contain self-intersections, slivers, small gaps, or non-manifold surfaces, while also ensuring robust union Boolean operations. This capability streamlines the geometry preparation process, making it significantly easier to modify designs and prepare them for simulation without encountering common meshing failures.
Benefits
When working with CAD or STL models, imperfections such as small gaps, self-intersections, sliver faces, and non-manifold surfaces often prevent successful meshing. Additionally, many CAD models are designed for manufacturing rather than simulation, meaning they may contain excess details such as internal components, bolts, and fasteners that can complicate the meshing process. Shrinkwrapping addresses these issues by automatically generating a watertight representation of the geometry, ensuring that meshing can proceed smoothly.
Another key advantage of shrinkwrapping is its ability to enhance Boolean operations, particularly when you need to swap components in a design. For example, when adding or replacing features such as different door handles or spoilers on a car, traditional Boolean operations may fail due to inconsistencies in the underlying surfaces. Shrinkwrapping resolves these challenges by creating a unified, meshable model that ensures successful modifications and downstream analysis, allowing designers to confidently iterate on their designs without worrying about meshing failures.
How to Use Shrinkwrap
There are two primary ways to enable shrinkwrapping in Luminary:
Checkbox for continuous CAD: If your geometry is continuous, you must check the Convert to discrete representation checkbox in the File Upload dialoge before attempting to use shrinkwrap. This preprocessing step ensures that the shrinkwrap operation functions correctly. If the checkbox is not selected before running shrinkwrap, an error will occur. A known issue is that the shrinkwrap button remains enabled even if the checkbox was not selected, but this is being addressed in an upcoming fix.
2. Shrinkwrap for STL imports: When importing STL files, select the shrinkwrap button in the geometry tab toolbar.
Controls
Shrinkwrapping provides you with some basic controls to fine-tune the process:
Select volumes to wrap: Instead of applying shrinkwrapping to the entire model, you can focus on specific regions or problematic parts. This targeted approach helps optimize processing time and ensures that only necessary modifications are applied.
Choose a resolution: The resolution setting dictates the level of detail captured in the shrinkwrapped model. A finer resolution results in greater accuracy but increases computational time. To balance efficiency and quality, it is recommended to start with a coarse resolution and incrementally refine it until the desired level of detail is achieved.
Best Practices
To maximize the effectiveness of shrinkwrapping, consider the following best practices:
Apply shrinkwrapping before creating a far-field boundary. The current implementation does not apply wrapping to the far-field Boolean operation, meaning it may fail if the geometry is not clean/watertight.
Use shrinkwrapping to resolve common geometry issues. These include non-manifold volumes, open surfaces, self-intersections, and unmeshable surfaces. By applying shrinkwrapping early in the workflow, you can mitigate these challenges and ensure a smoother meshing process.
Limitations
While shrinkwrapping is powerful, there are some limitations to be aware of:
Robustness limitations: Although the feature is continuously being improved, there may still be cases where shrinkwrapping fails. If this occurs, experimenting with different resolution settings may help resolve the issue.
Surface mesh artifacts: Depending on the chosen resolution, the shrinkwrapped surface may exhibit minor artifacts. Ongoing development efforts aim to enhance both the robustness and precision of the shrinkwrapping process to further improve results.
If you encounter geometries that consistently fail the shrinkwrap process or have unsuitable artifacts, our engineers would love to analyze these cases to improve robustness. Please reach out to support and we’d be happy to help.
By leveraging shrinkwrapping, you can overcome common geometry-related challenges, streamline your simulation workflows, and achieve more reliable meshing outcomes.