Random Wind Tunnel and Smoke Pictures Thread

[gone-ot]

A pull-cord (the little white plastic dangle seen in the below picture) winds a spring that rotates the inner excelsior aspen wood pad. My parents had one on our 1955 Ford Station Wagon. It had to be pulled to rewind the spring every 10-15 minutes.

[freebeard]

Mine didn't have that, maybe that's why it didn't work.

Originally Posted by kach22i

I know we have discussed this concept before, but have been unable to retrieve that old thread.

I tried 'swamp' in the internal search. One example:

http://ecomodder.com/forum/showthrea...tml#post346924

[kach22i]

https://tianyizf1.wordpress.com/

VGs on car roof to reduce separation

http://www.ramrebelforum.com/forum/w...ood-vents.html



http://ecomodder.com/forum/showthrea...g-30594-5.html

[kach22i]

I had a couple of window tabs open when this happened, some annoying audio automatically came on at full volume.

I suspect it was this link below, might want to turn off your speakers to be on the safe side, hope it's nothing nasty and just an advertisement.

11 GIFs that shows how car aerodynamics work : (wind tunnel testing)
https://www.carthrottle.com/post/nrgg7j6/

[kach22i]

Aero-tuning the Championship-Winning NASCAR Dodge Trucks

I asked Reynard to put it on the model on the moving ground plane wind tunnel at Shrivenham, and to push compressed air down through the stinger [see photo], which is the device that holds the vehicle in relationship to the moving ground plane in the right place to blow through a simulated radiator. They made a nice little radiator on the quarter-scale model.

[kach22i]

A bunch of images in this PDF below, not really "wind tunnel" related but dealing with aerodynamics just the same.

What this 2011 paper did was make me aware of another side of automated self-driving cars, not so much fitting more on the road to ease traffic, but the aerodynamic advantages of drafting. It is very convincing, at least it was for me. Three vehicles bumper to bumper 6-7% reduction in fuel consumption. Not earth shattering, but an improvement.

https://gcep.stanford.edu/pdfs/ChEHe...0_11_trans.pdf



Unrelated:

http://www.theoildrum.com/node/5912

[freebeard]

What this 2011 paper did was make me aware of another side of automated self-driving cars, not so much fitting more on the road to ease traffic, but the aerodynamic advantages of drafting. It is very convincing, at least it was for me. Three vehicles bumper to bumper 6-7% reduction in fuel consumption. Not earth shattering, but an improvement.

I can't find the story I saw that said hue-mon drivers won't abide being tailgated by autonomous vehicles. Maybe it's in here somewhere: https://www.google.com/search?q=auto...car+tailgating

This Popular Mechanix article says just a few autonomous vehicles can alleviate phantom traffic jams: Just a Handful of Self-Driving Cars on the Highway Could Cut Traffic Jams by Half
______

The Dodge pickup has a counter-flow radiator?
______

On-topic: tuft testing


http://forums.pelicanparts.com/off-topic-discussions/125505-more-random-pics-4042.html#post9316345

[gumby79]

Originally Posted by freebeard

The Dodge pickup has a counter-flow radiator?
______

The Dodge team introduced the 2pass radiator. Oriented front core then back core. To improve effectiveness and reduce the size of the required radiator opening =lower cd and more downforce. The team had an edge for 2-3 races. Then all teems were running them. Suspension of a mole. From article.
Then they Steped up there game and tryed to do a reverse air flow. But NASCAR ban the confidential idea before they could work the bugs out ,with a threat to ban the teem if they tryed something crazy like that agen.
I ran across the artical in Jan. made this suggestion:

Instead of blowing through the grill make it solid and vent behind a trip edge (basically a slightly oversized boddy gap on the perimeter of the grill). Into a low pressure zone . air flow is the result of pressure differential.

Alas, that’s all over and done now… a nice idea. Was the response. Threat of banishment kills a good Idea that could have worked its way into production cars.

[freebeard]

Thanks, but I'm not getting that at all. 2pass was a different, previous effort?

My best effort would be — suck air out of the front wheel wells [to smooth flow down the sides] and pump it mechanically into the stagnation point so the heated air energizes the airflow over the windshield. Close?

[gumby79]

Originally Posted by freebeard

Thanks, but I'm not getting that at all. 2pass was a different, previous effort?

My best effort would be — suck air out of the front wheel wells [to smooth flow down the sides] and pump it mechanically into the stagnation point so the heated air energizes the airflow over the windshield. Close?

They went to CNR Radiators to get these fabricated and manufactured, and then CNR took the design and told all the other NASCAR teams about it, so they built them for the other NASCAR teams so there’s no advantage there. But we had an advantage for a race or two.

Like this.

We turned the fan blades around and put them in a cowled duct, which you’re allowed to do, and blew the air through the radiator out the front. So instead of allowing air through the radiator from the front of the car into the engine bay, we forced the air out of the engine bay, drawn through the wheel houses, and also filled in the boundary layer over the body surfaces, cutting down drag.

The problem they ran into was suspected to be belt slippage. At speeds way above those experienced by an Ecomodder. He suggested a cog belt ,similar to a blower or dry sump oil pump as a potential ****ion. He was forbidden to do further any testing by Nascar, thank you Mole.
Hope this helps