It turns out that preparing geometry models for 3D printing has a lot of similarities with preparing geometry for Computational Fluid Dynamics (CFD). Both require watertight non-manifold geometry, otherwise your model will plunge your 3D printer or your CFD software into chaos.

Airflow CFD Simulation Around the Smithsonian Air and Space MuseumStreamlines

Given a 3D printable model, the CFD simulation process is relatively straightforward.

Watertight and Non-ManifoldSketchUp model prepared for 3D printing

Simply subtract the non-manifold model from a surrounding volume of air and your geometry is done.

CFD Flow Volume

Then it is a small step to set up the substance, assign boundary conditions, and run the simulation.

CFD Simulation ResultsVelocity contours

SketchUp is a popular application to prepare models for 3D printing and that same process is directly applicable for CFD model preparation. Then the big question is how do you use SketchUp to create a non-manifold model? Lucky for us there is a how-to blog post and video to help.

SketchUp 3D Printing Preparation

Notes

• The original SketchUp model of the Smithsonian Air and Space Museum is available on 3D Warehouse.
• Caedium was used to create the watertight flow volume, set up the substance, assign the boundary conditions, and finally run the simulation.