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Old 01-03-2021, 10:38 PM   #51 (permalink)
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I'm going to try mini aluminum VGs, and just wear earplugs if it doesn't help.
I blame howling wind wings for my tinnitus. Are your door window seals in good shape?

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Old 01-04-2021, 07:47 PM   #52 (permalink)
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Originally Posted by freebeard View Post
I blame howling wind wings for my tinnitus. Are your door window seals in good shape?
Yup, they are. As far as I can tell, the somewhat sharp edged A pillar is the only feature on the car that would produce this kind of howling, as everything else is fairly smooth and gently tapered. The noise is obviously louder when I move my head towards either A pillar. I'm hoping VGs will make the flow around the A pillar hug the body closer and reduce noise. Drag is probably a wash at best, but this car already has a 0.27 Cd or something so I'm not complaining.

On my first MR2 Spyder, I had a really bad howl that made my ears ring. I noticed a seal was poking out 2mm, so I hammered it down, and the howl went away. Of course, that car was still crazy loud and probably damaged my hearing quite a bit, but at least my ears stopped ringing.

On this car, nothing is poking out, and all the seals work. The mirrors are quiet (no noise difference when folding them in, taping them in various ways, etc.) and look pretty aerodynamic. It's gotta be the A pillars.

It's not all that bad, road noise is significantly louder up till around 60mph, then it gets really irritating.
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Old 01-10-2021, 10:21 AM   #53 (permalink)
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Julian, how did you attach the device to the A pillar ?

I was planning on creating somerhing similar, but it would have inner supports that would guide the airflow ( in a way, combining your two designs into one.
( In other words, the supports that would hold the vane in place would hopefully guide the air. It would be an air curtain.)

Since I brought up air curtains, I also wanted to ask why they are only found on the front wheels of vehicles.
This may not be such a concern for cars, but I notice air curtains are absent on Chevys' Silverado pickup, which has them on the front only.
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Old 01-10-2021, 01:40 PM   #54 (permalink)
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Originally Posted by Cd View Post
Since I brought up air curtains, I also wanted to ask why they are only found on the front wheels of vehicles.
This may not be such a concern for cars, but I notice air curtains are absent on Chevys' Silverado pickup, which has them on the front only.
The Silverado currently has the largest air curtain ducts on any production vehicle--they're more than a foot tall IIRC (I measured them at an auto show in the Before Times), and about twice as tall as those on its platform mate, the GMC Sierra.

There are only three cars with air curtain ducts at the rear: the Lexus LC, Honda Clarity, and Hyundai Veloster N (not N-line).
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Old 01-10-2021, 04:04 PM   #55 (permalink)
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Originally Posted by Cd View Post
Julian, how did you attach the device to the A pillar ?

I was planning on creating somerhing similar, but it would have inner supports that would guide the airflow ( in a way, combining your two designs into one.
( In other words, the supports that would hold the vane in place would hopefully guide the air. It would be an air curtain.)
I used a steel rod through the opening in the middle of the aerofoil, threaded at each end and with a dome nut on it. I made end plates from ABS plastic with folded flanges. The flanges were stuck to A pillar with tape for testing, and would have been attached via double-sided tape had I kept them in place. By loosening the nuts, I could change the angle of the vane. So basically the same approach I took on my Edgarwit front air curtains.

Not a very clear pic (lots of cropping) but you should get the general idea:



Just to reiterate, in my testing using simple curved vanes (not aerofoils) didn't work.

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Since I brought up air curtains, I also wanted to ask why they are only found on the front wheels of vehicles.
This may not be such a concern for cars, but I notice air curtains are absent on Chevys' Silverado pickup, which has them on the front only.
I haven't tried them at the back myself (no need with the Insight's rear wheel opening spats) but I would guess this. Manufacturer-style air curtains make use of the high pressure available at the front of the car. There's no such high pressure available in front of the rear wheels. Therefore, they need to be more 'guides' than front-style air curtains. I would imagine that for these guides to work, they need to be using hardware (scoop, etc) that (1) is working in attached flow, and (2) is wider than the boundary layer.

I would think for amateurs it would be easier just to cover the back wheel opening with a spat.
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Old 01-11-2021, 02:30 PM   #56 (permalink)
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I would think for amateurs it would be easier just to cover the back wheel opening with a spat.
I believe the Gen 1 Insight has what we (in the US) call “fender skirts” where part of the wheel opening is covered and “spats” has been used on this forum to describe the tire deflectors used in front of the tires. (Front Deflectors? p. 158 in Julian’s book). There has been some confusion about this term in the past here. I think it would be helpful if we could agree on what we are calling the various mods we try. I am happy to defer to the experts.
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Old 01-11-2021, 02:53 PM   #57 (permalink)
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Originally Posted by COcyclist View Post
I believe the Gen 1 Insight has what we (in the US) call “fender skirts” where part of the wheel opening is covered and “spats” has been used on this forum to describe the tire deflectors used in front of the tires. (Front Deflectors? p. 158 in Julian’s book). There has been some confusion about this term in the past here. I think it would be helpful if we could agree on what we are calling the various mods we try. I am happy to defer to the experts.
Wheel spats have been used to indicate external wheel covers for a very long time - in aircraft, back to at least the 1930s.

I have never seen spats used to describe tyre deflectors except here.
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Old 01-11-2021, 03:26 PM   #58 (permalink)
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Spats (footwear) - Wikipedia
Search domain en.wikipedia.org/wiki/Spats_(footwear)https://en.wikipedia.org/wiki/Spats_(footwear)
Spats, a shortening of spatterdashes, or spatter guards are a type of classic footwear accessory for outdoor wear, covering the instep and the ankle. Spats are distinct from gaiters, which are garments worn over the lower trouser leg as well as the shoe.
"tyre[sic] deflectors" is generic. Local to me, planes have pants and cars have skirts. Rather than 'deflector' I'd say the OEM efforts are merely a wickerbill.
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Old 01-11-2021, 03:35 PM   #59 (permalink)
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"tyre[sic] deflectors" is generic. Local to me, planes have pants and cars have skirts. Rather than 'deflector' I'd say the OEM efforts are merely a wickerbill.
"Wickerbill" is another term I'd never heard of - eg never seen in any formal tech aero reference - until I came here. I still don't know what it's supposed to be.

Wikipedia says a wickerbill is a Gurney flap on a wing.
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Old 01-11-2021, 03:37 PM   #60 (permalink)
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Originally Posted by freebeard View Post
"tyre[sic] deflectors" is generic. Local to me, planes have pants and cars have skirts. Rather than 'deflector' I'd say the OEM efforts are merely a wickerbill.
And if you want to see wheel spats, look here.

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