Aerodynamic simulations for Toyota Tacoma

[Varu]

Hi all,

Before attempting to build or buy an aerodynamic truck cap, I decided to do some simulations using Chernyshenko's popular program.

Here are the results:

http://www.youtube.com/watch?v=3uhBy4CYMAc

Enjoy...

[some_other_dave]

Your slanted cap had leftover pixels from the full cap; note the pink high-pressure areas right around where the upper-rear corner of the cap was. Those create lots of drag, but are probably not going to be there with an actual slanted cap...

-soD

[Varu]

Originally Posted by some_other_dave

Your slanted cap had leftover pixels from the full cap

I checked and there are no leftover pixels. (See attached.)

Maybe the vorticity spots are caused by the sharp corners of the slanted cap?

[ChazInMT]

Varu...First off, most excellent stacking of the Flow Illustrators, how did you do that? I'd love to be able to do the same to compare different renderings.

Next, I looked DEEPLY at your bit map.....and there are a shat load of pixels drifting about. No biggie, just next time, use your eraser really good. Flow Illustrator sees anything which isn't white (Really white) as solid. I use Paint to make my .bmps, there is a function there under, Image/Attributes to select B&W which I always do. That way no gray scale artifacts show up.

I have gotten really good using the Draw feature in Word to make outlines. Once you get used to it, Draw is super easy to trace out complex curves on a photograph. I can trace a car in about 7 Minutes. Then it is easy to cut & paste the drawing into paint, B&W it and tadaaa.

[Varu]

Originally Posted by ChazInMT

Varu...First off, most excellent stacking of the Flow Illustrators, how did you do that?

Stacking takes a little effort. You have to write a script for Avisynth and then open that in Virtualdub. But... the videos produced by the website use the Indeo 5 codec, which is no longer free (Vista lacks the codec anyway). You can convert them to something useful using ffmpeg.

More info about stacking at virtualdub dot tk....

Regarding the pixels, wow I stand corrected. At 600% zoom in Paint I can see there are indeed many gray pixels in there. Oops

By the way, Chernyshenko's server is giving errors at the moment. When I tried to upload by bmp file I got "There is not enough space on the disk. : File could not be uploaded." Presumably a temporary problem.