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Old 08-13-2013, 03:03 AM   #164 (permalink)
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00C - '00 Toyota Corolla
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Radius box lid to defeat locked vortex?

Originally Posted by aerohead View Post
It looks like the air is making the 'jump' really well across the locked-vortex between Kamm rear edge and beginning of down-slope on the box.
The flat top area of box is the only area with reversed flow,indicative of the vortex swirling in towards the backlight.All good!
Hucho prefers long,shallow -angled diffusers.I suspect that the tufts underneath are kinda telling on that.
With concessions to driveway clearance and such we'll have to be 'practical' in this department.
Thanks for the pics and videos!Nice project evolution.
I'm glad you're seeing the same things I am. Maybe I'm learning something.

(I have another thought on the diffuser though... when I remember to actually do it, I want to put up a photo of the car's rear-quarter-underbody. To my eye it looks horrible.)

I was wondering if the locked vortex could be a consequence of the excessively-sharp transition on the lid.

This morning I tufted the same rig again, but with the addition of some foam pieces to soften the curve.

Unfortunately, I forgot about the contrast thing again. I ought to carry a dark can of spray paint when I go out for tufting to help with my absent-mindedness. Or maybe I should have splurged and got some fluorescent yarn when it was suggested...

When I briefly reviewed the vid this morning I thought it was a failure. But after reviewing it frame-by-frame I realized that the second row of tufts actually spend most of the time facing the right way.

So maybe this is a solution that can attenuate the locked vortex and minimize energy loss there. (But probably I should add some black paint and re-tuft, and do a better job placing tufts... soon...)

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