Wind Tunnel – MSAFluid [openFrameworks]

Below is a collection of ‘Wind Tunnel’ experiments created by Jason McDermott. The openFrameworks application uses Memo Akten’s MSAFluids library (part of MSALibs) which has recently been updated and also ported to Cinder. I have included most of Jason’s movies below showing the development from the first MSAFluid example to the latest experiments simulating wind tunnel scenario. Of course, we don’t expect these to be used to airplane design anytime soon but they are absolutely wonderful to look at …and play with (thanks Jason).

Jason writes:
The first versions used the ofVertex(x,y) method to draw a bezier curve, describing a shape outline to locate the forces – which was useful for doing simple outlines of physical objects – but fell short of simulating pseudo-3D objects. This latest version includes a series of points which describe a field of forces, as depicted by the grid of cyan pixels.

Jason McDermott is an architecture graduate, design tutor and an interactivation design researcher. Jason now works at Arup in Informatics with Dan Hill (aka cityofsound).

MSA Fluids (OpenFrameworks) from Jason McDermott on Vimeo.

MSA fluids demo application, using sample code and made in openFrameworks. Rendered using the ofxMovieSaver addon, see here for more

Wind Tunnel Sim (openframeworks) from Jason McDermott on Vimeo.

Test rendering of a wind tunnel sim, using Memo Aktens MSA Fluid lib. An invisible sphere is located in the wind tunnel, surrounded by a simple particle flow visualisation.

Wind-Tunnel simulation (openframeworks) from Jason McDermott on Vimeo.

Early test for a wind-tunnel simulator, built in OpenFrameworks and using the MSAFluids library. This test uses 9 forces to push particles across the screen. Voticity confinement is turned on, also note the colour cycling on each force position.

Update: I’ve since discovered a better technique is to manipulate the fluid cells themselves using the ” int index = fluidSolver.getIndexForCellPosition(forcePosX,forcePosY);
fluidSolver.u[index]+= 0.001;”
method.

Wind Tunnel simulation (Openframeworks) from Jason McDermott on Vimeo.

Wind tunnel sim, made with Openframeworks using Memo’s awesome MSA Fluids library. Wing shape can be deformed and modified live, along with wind speed and object ‘force’.

Next steps will include more complicated shapes, ‘completed’ beziers and a few more controls.

Wind Tunnel Simulator V3 from Jason McDermott on Vimeo.

The latest version of my wind tunnel sim, this time round I’ve included draggable handles on a completed polygon made from bezier curves.

Fun!

Next steps? I’d like to combine this with something like box2d to get all points within the polygon creating a force on the fluid (not just the outline). Not sure what else, perhaps a centroid with angle of attack for the object.