Random Wind Tunnel and Smoke Pictures Thread

[ChopStix]

Originally Posted by ChopStix

Those pic's were taken by my active duty friend while in Germany. They had the F35 at an airshow. Between the wingtip vortices and the clouding effect they are really cool pic's.

Wingtip vortices, not contrails. My bad.

[freebeard]

Wingtip vortices, not contrails. My bad.

Don't be so hard on yourself.

This phenomenon is why modern airliners have the upturned wingtips. See also Prandtl V wing

https://en.wikipedia.org/wiki/Lifting-line_theory

Interesting fact:

According to the Helmholtz theorems, a vortex filament cannot begin or terminate in the air.

https://en.wikipedia.org/wiki/Horseshoe_vortex

The horseshoe vortex model is unrealistic in that... In a more realistic model, the lifting-line theory, the vortex strength varies along the wingspan, and the loss in vortex strength is shed as a vortex sheet all along the trailing edge, rather than as a single trail at the wing-tips

So there is a vortex sheet off the entire trailing edge with vortexial pinwheels at the tips.

[ChopStix]

Don't be so hard on yourself.

In this case I knew the difference. I just didn't look at the pictures close enough.
So yeah I was a dum-bass on this one.... (-lol)


Here's a nice example of a brick shaped rear end.

[ChopStix]

[kach22i]

At the 4:40 mark video coverage of a Porsche 911 turbo whale tail in wind tunnel.

Porsche Top 5 – Bonus episode: Your most wanted models
https://www.youtube.com/watch?time_c...&v=c0VsZzGmDI8


One this one, starts at the 2:00 mark, and lasts just a minute.

Porsche Top 5 – Weissach’s toughest functionality tests

https://www.youtube.com/watch?v=mQ91HPyt_c4

[kach22i]

https://www.ecoological.com/improved...rformance.html

[kach22i]

https://newsroom.porsche.com/en/moto...ity-14359.html



2018 porsche gt3 wind tunnel pr
http://www.autobics.com/2017/10/2018...ind-tunnel-pr/

[kach22i]

https://www.pinterest.com/jomasan/analysis/


Following the link:

http://www.deansgarage.com/2009/gm-w...-and-brochure/

Before the GM Wind Tunnel was constructed, scale models would be shipped to a tunnel in California (maybe CalTech, I don’t remember). The black dots are from ink put on the model and the trails trace airflow on the surface. Back in those days GM could afford Polaroid film.

[kach22i]

Flow Design
Virtual wind tunnel testing simulation tools
https://www.autodesk.com/products/flow-design/overview

Flow Design virtual wind tunnel software simulates airflow around buildings, vehicles, consumer products, and other objects.

https://www.autodesk.com/products/flow-design/overview


Short demonstration videos in link above...............looks very interesting.

[kach22i]

Climb Inside the World's Largest Wind Tunnel
https://www.wired.com/2017/02/climb-...t-wind-tunnel/

The engineers call this space "the 80-by-120;" it's the largest wind tunnel on the planet, 80 feet tall and 120 feet wide, big enough to hold a Boeing 737, the star of the National Full-Scale Aerodynamics Complex in Mountain View, California. The truck is Navistar's "Catalist," a concept built to cut drag and boost fuel efficiency. The 80-by-120 is one of the few places that can really put the new design to the test.