boat tailing behind wheels
 

anyone have an idea of how much of an impact boat tailing behind wheels has?

was thinking of adding some behind the wheels on my ioniq when i do the under tray
was thinking of cutting and rounding these foam wedges behind the wheels. firm enough to hold shape, but soft enough to take impact if something wacky happens
https://m.media-amazon.com/images/I/...AC_SL1500_.jpg

Once they're cut and rounded which way would be up? I could see it with 3" wide tires.

The hive mind says conveyor belting.

what do you mean? id put them behind the tires and gorilla glue the to the under tray. id cut them to be the same width or a little narrower than the tires

Well, not that I care; but the question was would a square, rectangular or triangular face be uppermost?

How wide is the tire?

rear wheel fairings
 

Volkswagen will build its ultra-frugal XL1Find the image of the 2013 Volkswagen XL1, and look at what they did.
Your wheel skirts could be low enough that they integrate right to the leading edges of the fairings.
A look at the book, 'The Leading Edge', by Goro Tamai, of MIT's solar race car team would be a look at the wheel fairing candy store!;)
7th image from top:

The xl1 is where I’m modeling my idea after. They don’t really use them on the rear wheels. Only boat tailing on the front mostly

rear
 

Actually, they do have boat-tails behind the rear tires, as well as the fronts, and in front of the rear tires.
All a good thing!:)

Still not seeing an XL1 fairing with that little material.

not
 

1)They had very little rear overhang to work with, but used all they had within the constraints of the diffuser.
2) And, as per the J-form/K-form testing @ FKFS, Volkswagen shaped what they had exactly as per best practices for a two-dimensional flow section, as observed for lowest drag.
3) If they'd had more aft-body, they could have had more drag reduction.
4) In HVAC practice, one needs ' six pipe-diameters' ( tire width ) distance downstream of an 'obstruction'( tire ) in order for the streamlines to recover.
5) Many solar race cars take full advantage of the car's 'real estate.';)

Sounds excessive, a six inch tire would need a three foot tail. HVAC is an inverse case. Mair found an l/d of 1.0 gets 80% of the maximum.

three feet
 

https://hum3d.com/3d-models/honda-dream-solar-car-1996/Things are what they are.
This is 'wing'/ 'strut'/ 'section' stuff. Two-dimensional flow, where otherwise 'excessive' fineness ratios are king.
Solar racers will put three feet behind a one-inch bicycle tire. Cd 0.10.
Mair's metrics were only for three-dimensional flow. Peregrine falcons.:)

Uh I’m just asking if the foam wedges would be decent and if anyone knows of any studies or tests that show a reduction in drag with the boat tailing behind wheels versus examples of cars using them

Here’s an underside pic of the wheel deflectors in FRONT of the rear wheels on the Porsche taycan with a cd 0.22. Interesting how they do a boat tail into the deflectors, versus just flat deflectors like other cars. Even the Ioniq has small flat deflectors. Also since they are boat tailing in front of the wheels, why wouldn’t Porsche do the inverse behind the wheels? Even xl1 did it and Porsche wanted a low drag EV. Would be interesting to hear from the engineers

This is what Toyota did behind the rear wheels on the 2nd gen Prius.

Here is a drawing from 2013. For a pickup, but it could be scaled to the size of the Porsche Taycan part.

https://ecomodder.com/forum/member-f...42-mudflap.jpg

Two U-shapes fastened only on the two long edges.

[Why do all the news stories about Paul Pelosi leave out the most important detail, what model 2021 Porsche was he driving?]

did they do it for the front wheels?

Nice!
I'm wondering, why didn't they do that for later gen Prius or other models?

No, just the rear.

That is a good question. Heck why doesn’t Tesla do it?

any studies
 

Sighard Hoerner's, 1951, 'Aerodynamic Drag' has hundreds of solutions with 'boat-tailing'.
So does Wunibald Kamm's/ Koenig-Fachsenfeld's research from early 1930,s FKFS, to around the time of Pearl Harbor, ending 'streamline cars.'
'The Leading Edge', by Goro Tamai.
Ignore the fact that it's a 'tire-wheel' that you're streamlining.
The 'width' of the system determines all other dimensions.
And the 'system' needs to 'enclose' the excrescence. This defines the 'width.'
The 1993 HONDA Dream solar racer is an example of an ideal wheel fairing package.

simple rear wheel fairings
 

Not sure if this will link. If it does, it's cedar, open cell polystyrene foam, brushed-on polyurethane barrier coating to protect foam from polyester-based filler, BONDO, primer ,paint, back-fastened wheel fairings behind SPIRIT's rear wheels, attached from the top down.https://ecomodder.com/forum/attachme...4&d=1249763104

DIY trailer wheel fairing construction
 

https://ecomodder.com/forum/attachment.php?attachmentid=9554&d=1318705563I used the same technique on the trailer. Ultimately, they'll get inside and outside skirts.
https://ecomodder.com/forum/showthre...-t-7839-5.html
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https://ecomodder.com/forum/attachme...p;d=1255812123
https://ecomodder.com/forum/attachme...p;d=1296337358

video
 

Thanks Vekke, that's probably as close as I'm likely to get to the car.:p

I have once sat in at fair when it was launched and my head was hitting the roof if I moved even little. I am 193cm tall. I will try to ask for test drive and better place to take pictures. Today had toddler in my lap in harness so could not take any measurements of the car just rough estimate and few pictures.

I shall revise my suggestion from 2013. The U-shaped metal bracket becomes a[n Italic] V-.

https://ecomodder.com/forum/member-f...42-mudflap.jpg

The open end could evern be drifter stitched.