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Old 11-25-2020, 01:51 PM   #124 (permalink)
aerohead
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pressures

Quote:
Originally Posted by JulianEdgar View Post
As in, the template is the greatest misapprehension here - but what is the next greatest?

Without a doubt, the significance and action of aero pressures acting on panels.

When Vman455 showed some of the measured pressures on his Prius (data that immediately contradicted much of what Aerohead spouts), I was amused to see no-one actually 'got' the contradiction (or no-one who commented, anyway). I was amused but not surprised - because the same thing happens here when I show my Insight's measured body panel pressures.

Aerohead's ideas in this area are again quite wrong, and again they seem to have been adopted widely here. And - yet again - it's because people don't make measurements - if they did, they'd soon see reality for themselves.

A good example is the person from this group who commented on my 'don't use a template' video. He looked at the Jaguar's CFD pressures (shown in the video) and had them completely reversed! That's sure some misunderstanding.

And I might add, the reason for that complete misunderstanding can be related back to the silly template - you could see that's what he was trying to build his ideas on. But crap in = crap out.
* Without a zero-separation reference pressure profile datum, from which to compare, there's no 'context' with which to qualify the significance of any pressure measurements you provide.
* From CAR and DRIVER's 'Drag Queens' article, the Nissan LEAF is the only 'template' car tested.
* The LEAF had lower rear lift than the PRIUS ( a sub-'template' form )
* The lower lift of the LEAF can be explained only by higher pressure acting over the aft-body.
* Had the flow actually been attached on the PRIUS, it's rear lift would have been less than the LEAF.
* The only explanation possible is, that the PRIUS is experiencing flow separation. Just like the 2010 Audi A7 Sportback. 2020 Porsche Taycan.
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