02-26-2021, 09:56 PM
|
#1 (permalink)
|
Ultimate Fail
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
|
Window screen used as a skin on vehicles sensitive to crosswinds ?
Has the topic of window screen used as a skin on vehicles been discussed recently ?
This provides a surface for air to skip over, but also one that allows crosswinds to pass through.
There is a large metal chainlink fence at my job.
It takes maybe 30 lbs of force to close it, yet even a moderate breeze will cause it to slide on its railing and slam shut.
I know some of you sail boats.
I had no idea that wind would have so much pull on such a small surface area.
|
|
|
The Following User Says Thank You to Cd For This Useful Post:
|
|
Today
|
|
|
Other popular topics in this forum...
|
|
|
02-26-2021, 10:59 PM
|
#2 (permalink)
|
Master EcoModder
Join Date: Aug 2012
Location: northwest of normal
Posts: 28,520
Thanks: 8,073
Thanked 8,870 Times in 7,322 Posts
|
I've always wondered about this. Mainly for bellypans.
Quote:
Anisotropy
Anisotropy is the property of a material which allows it to change or assume different properties in different directions as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physical or mechanical properties An example of anisotropy is light coming through a polarizer. Another is wood, which is easier to split along its grain than across it.
More at Wikipedia
|
Years ago I posted a link on Ecomodder to a study that showed a cattle truck with round holes at the front of the sidewalls was better than the rectangular horizontal slots that are more common (at preventing suffocation of the livestock!)
Window screen is flexible. Were you thinking of using it for daylight openings?
It's all holes. Maybe a perf metal with some arbitrary hole size and spacing is optimal?
So many questions. When I was in high school and college I worked summers in a feed & seed mill. They had stacked graduated stainless steel screens about 4x6 feet in a shaker for sorting mill run into different seeds. hole sizes below an inch or so.
The place burnt down a decade or two ago.
__________________
.
.Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster
____________________
.
.Three conspiracy theorists walk into a bar --You can't say that is a coincidence.
|
|
|
02-27-2021, 11:10 AM
|
#3 (permalink)
|
Somewhat crazed
Join Date: Sep 2013
Location: 1826 miles WSW of Normal
Posts: 4,360
Thanks: 526
Thanked 1,188 Times in 1,048 Posts
|
Aren't dimples on a golf ball massive screen holes?
|
|
|
The Following User Says Thank You to Piotrsko For This Useful Post:
|
|
02-27-2021, 11:19 AM
|
#4 (permalink)
|
マット
Join Date: Nov 2015
Location: Indiana
Posts: 718
Thanks: 131
Thanked 258 Times in 188 Posts
|
I was actually thinking about how maybe you could use it on the belly pan to cover the exhaust. Maybe at speed the air would flow past while at slower speeds it would be able to breath?
__________________
1973 Fiat 124 Special
1975 Honda Civic CVCC 4spd
1981 Kawasaki KZ750E
1981 Kawasaki KZ650 CSR
1983 Kawasaki KZ1100-A3
1986 Nissan 300zx Turbo 5 spd
1995 Chevy Astro RWD (current project)
1995 Mercury Tracer
2017 Kawasaki VersysX 300
2022 Corolla Hatchback 6MT
https://www.youtube.com/channel/UC6s...LulDUQ8HMj5VKA
|
|
|
02-28-2021, 12:59 PM
|
#5 (permalink)
|
Ultimate Fail
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
|
Quote:
Originally Posted by M_a_t_t
I was actually thinking about how maybe you could use it on the belly pan to cover the exhaust. Maybe at speed the air would flow past while at slower speeds it would be able to breath?
|
Like a breath of fresh air, I would breathe a sigh of relief, if the breathing would be improved by the window screen.
The good thing about window screen, is that even if it rips and falls from the underside of the car, it doesn't have enough mass to damage anything.
It would have to be replaced often though if driven on roads with lots of debris.
|
|
|
03-01-2021, 09:56 PM
|
#6 (permalink)
|
Master EcoModder
Join Date: Dec 2016
Location: Florida
Posts: 475
Thanks: 80
Thanked 217 Times in 179 Posts
|
Quote:
Originally Posted by freebeard
I've always wondered about this. Mainly for bellypans.
Years ago I posted a link on Ecomodder to a study that showed a cattle truck with round holes at the front of the sidewalls was better than the rectangular horizontal slots that are more common (at preventing suffocation of the livestock!)
Window screen is flexible. Were you thinking of using it for daylight openings?
It's all holes. Maybe a perf metal with some arbitrary hole size and spacing is optimal?
So many questions. When I was in high school and college I worked summers in a feed & seed mill. They had stacked graduated stainless steel screens about 4x6 feet in a shaker for sorting mill run into different seeds. hole sizes below an inch or so.
The place burnt down a decade or two ago.
|
I always thought the best everyday common material to have this property, was concrete, in that it has far greater strength in compression vs tension, approx 10:1.
|
|
|
03-03-2021, 01:16 PM
|
#7 (permalink)
|
Master EcoModder
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,256
Thanks: 24,382
Thanked 7,359 Times in 4,759 Posts
|
aren't ?
Quote:
Originally Posted by Piotrsko
Aren't dimples on a golf ball massive screen holes?
|
Only if it was a 'whiffle' ball. Porous.
Dimples provide a critical roughening, to trigger transition to a turbulent boundary layer, off the clubhead, at around 110-mph.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
|
|
|
03-03-2021, 01:26 PM
|
#8 (permalink)
|
Master EcoModder
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,256
Thanks: 24,382
Thanked 7,359 Times in 4,759 Posts
|
screen
Quote:
Originally Posted by Cd
Has the topic of window screen used as a skin on vehicles been discussed recently ?
This provides a surface for air to skip over, but also one that allows crosswinds to pass through.
There is a large metal chainlink fence at my job.
It takes maybe 30 lbs of force to close it, yet even a moderate breeze will cause it to slide on its railing and slam shut.
I know some of you sail boats.
I had no idea that wind would have so much pull on such a small surface area.
|
No porous surface can support airflow.
If the entire perimeter of the vehicle's underbody is 'dammed' ( airdams, rocker panels, and rear facia, dead air will be trapped within that footprint, and active flow will skip over ( under ) this stagnant, dead air, which travels along, like the forward stagnation bubble.
Cooling air, from the engine bay will contaminate this area. EVs have the advantage.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
|
|
|
03-03-2021, 08:16 PM
|
#9 (permalink)
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,864
Thanks: 0
Thanked 1,683 Times in 1,501 Posts
|
There would be a lot of compromises rendering such approach unsuitable. Even aircraft that still resorts to a fabric skin have it sealed, not leaving much room for the wind to go through. And for a car, other matters such as thermal comfort may be accounted, so even though a skin that allows some air flow in a simpler vehicle without HVAC might seem good in a summer afternoon it would become a PITA during winter or rainy days.
|
|
|
03-04-2021, 11:15 AM
|
#10 (permalink)
|
Master EcoModder
Join Date: Dec 2016
Location: Florida
Posts: 475
Thanks: 80
Thanked 217 Times in 179 Posts
|
Quote:
Originally Posted by aerohead
Only if it was a 'whiffle' ball. Porous.
Dimples provide a critical roughening, to trigger transition to a turbulent boundary layer, off the clubhead, at around 110-mph.
|
And one reason "whiffle" golf balls are so suitable for enclosed indoor space golf ball practice, with its extremely high drag.
I personally can't vision what the benefits here are with pourous aero surfaces like fence/screen, but then, I here to learn.
|
|
|
The Following User Says Thank You to j-c-c For This Useful Post:
|
|
|