Lightyear One - from solar racer to commercial product

[aerohead]

Originally Posted by Phase

So what’s the term for the rear edges that slightly extend out then cup back into the rear? Hyundai seems to call them “ separation traps” and a lot of the newer Toyotas have something similar below their tail lights. Eqxx and xl1 also so something similar at their rears too

* Do they extend 'out' to the rear, or extend 'out' axially, away from longitudinal 'center' of the car?
I never got anything out of any of the videos.

[freebeard]

I think no-one did it better than Caroll Shelby.


st.automobilemag.com/uploads/sites/11/2015/07/Shelby-Cobra-Daytona-Coupe-50th-Anniversary-rear-side-view.jpg

So what’s the term for the rear edges that slightly extend out then cup back into the rear?

Google fails me ....again.

Maybe aerohead will recall, there was an engineer at the Zepplin Works, a contemporary of Jaray, whose name is appartently not Fasenfeld/Fashenfeld/Faschenfeld, that was the original proponent.

One minute delta. [waves at aerohead]

[aerohead]

Originally Posted by freebeard

I think no-one did it better than Caroll Shelby.


st.automobilemag.com/uploads/sites/11/2015/07/Shelby-Cobra-Daytona-Coupe-50th-Anniversary-rear-side-view.jpg


Google fails me ....again.

Maybe aerohead will recall, there was an engineer at the Zepplin Works, a contemporary of Jaray, whose name is appartently not Fasenfeld/Fashenfeld/Faschenfeld, that was the original proponent.

One minute delta. [waves at aerohead]

* What is shown on Peter Brock's Shelby Cobra Daytona Coupe is simply a rear spoiler, which was introduced by Richie Ginter, at the 1961, 24-Hours of Le Mans, on the Team Ferrari entries, which he drove for. Ginter was a US Air Force guy, and was applying what he'd seen on military aircraft ( ailerons, flaps, slats, slots, etc..).
* Wolfgang Klemperer was a PhD candidate at the Zeppelin Werke, who conducted the wind tunnel tests for Paul Jaray, on the car models, and would go on to receive his doctorate in 1927, remaining at Zeppelin, then Goodyear-Zeppelin Corporation. I'm unsure about Klemperer and spoilers.
* Jaray invented the 'low nose, the 'ideal nose', the 'streamlined car', 'wheel skirts', the 'belly pan', the 'diffuser', the cambered , zero-lift underbody.
* Fachsenfeld invented the truncated tail, the 'splitter, ' racing wings, maybe more which escape me.
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The rear spoiler re-accelerates the flow, lowers the pressure to 'non-adverse' condition, allows re-attachment, pressure recovery, higher base pressure reduced pressure drag, reduced induced lift.
A kammback is better, but would add mass, alter the polar moment of inertia, reduce the power-to-weight ratio, reduce acceleration, and diminish the handling of a race car.
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By the way, Brock's tearing edge on his rear spoiler comes up 'exactly' to the AST-III.

[Phase]

Why don’t we use spoilers on the sides of cars too?

[Cd]

Originally Posted by Phase

Why don’t we use spoilers on the sides of cars too?

Have a look at the rear of the 1980 Camaro with it's ducktail spoiler.
The spoiler wraps around the sides of the car.
It also used side ' spoilers ' ( deflectors ) around the wheels.
I found it interesting that they had no effect on drag, but produced downforce when tested in the A2 windtunnel.

[Phase]

Originally Posted by Cd

Have a look at the rear of the 1980 Camaro with it's ducktail spoiler.
The spoiler wraps around the sides of the car.
It also used side ' spoilers ' ( deflectors ) around the wheels.
I found it interesting that they had no effect on drag, but produced downforce when tested in the A2 windtunnel.

It seems like the new Ioniq 6 is using little side spoilers but they are calling them separation traps

[freebeard]

The text and both pictures make no sense.

Maybe it's obvious in three dimensions?

[aerohead]

Originally Posted by Phase

It seems like the new Ioniq 6 is using little side spoilers but they are calling them separation traps

Finally a look at the enigmatic 'traps'!
The original radii may have created a bistable flow condition, causing the separation line to 'hunt.'
What would otherwise be called a 'trip-strip' to enable reattachment to a structure downstream ( which doesn't exist ), becomes a 'separation trap', akin to Fachsenfeld's tearing strip, which fixes the wandering separation in one place.
The Paris Dressmakers will do anything except the elegance of a proper, and superior Kamm-back.

[Phase]

Originally Posted by aerohead

Finally a look at the enigmatic 'traps'!
The original radii may have created a bistable flow condition, causing the separation line to 'hunt.'
What would otherwise be called a 'trip-strip' to enable reattachment to a structure downstream ( which doesn't exist ), becomes a 'separation trap', akin to Fachsenfeld's tearing strip, which fixes the wandering separation in one place.
The Paris Dressmakers will do anything except the elegance of a proper, and superior Kamm-back.

what would happen if i put those little spoiler sidelip separation traps on my ioniq?

[freebeard]

A-B testing would happen.