Random Wind Tunnel and Smoke Pictures Thread

[freebeard]

https://www.youtube.com/watch?v=Q5COAi6KM8o

If nothing else, it shows the pitch of the blades.

[kach22i]

Originally Posted by freebeard

If nothing else, it shows the pitch of the blades.

First time I've seen this phenomena when it was not an animated GIF or a still photo. Nice find.


http://www.arising.com.au/aviation/w...d-turbine.html

[gone-ot]

Articles on Vortex-Shedding will typically include pictures like this (FFA):



...like contained in this MIT paper:

http://ocw.mit.edu/courses/mechanica...lec20_viv1.pdf

[kach22i]

Glow with the Flow
Glow with the Flow | NASA

Researchers at NASA's Langley Research Center in Hampton, Va., use all sorts of tools and techniques to learn more during the development of aircraft and spacecraft designs.

In this photo, engineers led by researcher Greg Gatlin have sprayed fluorescent oil on a 5.8 percent scale model of a futuristic hybrid wing body during tests in the14 by-22-Foot Subsonic Wind Tunnel.

The oil helps researchers "see" the flow patterns when air passes over and around the model. Those patterns are important in determining crucial aircraft characteristics such as lift and drag.

Image Credit: NASA Langley/Preston Martin

[freebeard]

That's pretty psychedelic. I assume a high angle of attack.

My current favorite airframe is the Atlantica:

[kach22i]

Originally Posted by freebeard

.........Atlantica

I love that project, reminds me of all the clay models I made myself decades ago. Top imagine somebody bringing this concept to life is exciting to me.

I posted these pictures a few days ago, sort of hard to find them on the site.

Atlantica Blended Wing Body



Although the engine looks added as an afterthought, it is well placed. No direct path to ingest birds, easy serviceability and perhaps even some acoustic advantages compared to other locations.

History:
Genesis Of Aircraft

If you like aircraft, check out this incredible Blog (many pages and entries):
https://hushkit.net/page/5/

The guy has a hilarious sense of humor too, good reading.

EDIT: Found this post, combing this thread with the sidebar discussion:

A Strategic Advance in Another Direction - Page 2

A few days ago Alan Shaw sent an article to the Atlantica mailing list from the January 14. 2008 issue of Aviation Week & Space Technology. Somebody has been granted a patent for a center body airbrake for BWB aircraft. It's basically the flap I described with some holes to prevent the startup vortex from forming. Apparently the inventors were surprised that it enhanced lift, they were just looking for an airbrake.

Video posted in that thread is excellent, turn down the sound half-way though.

https://www.youtube.com/watch?v=ouF9Xkoi3uk

[kach22i]

Quite incredibly the topic this NASA article covers is not accompanied by an appropriate still photo, nor are such images in the poorly edited video.

Your government at work, guess you will have to just use your imagination.

For me this includes a 1980's dance floor with a crystal ball, strobe light and smoke machine.

Sept. 7, 2016
NASA to Shine Lasers on Future Aircraft Concept
https://www.nasa.gov/feature/langley...rcraft-concept

But for this test it looks a little different. The top of it has been painted in non-reflective matte black to accommodate laser lights that will sweep across the model in sheets. NASA and Boeing researchers will use those laser sheets combined with smoke in the technique known as particle imagery velocimetry or PIV. That will map the airflow over the model...................

So if engineers have to worry about airflow – why change where the engines are? Researchers say putting them on top of the plane helps shield noise, especially from people on the ground, and contributes toward NASA's goals of developing greener, quieter planes.

[kach22i]

April 22, 2016
NASA Moves to Begin Historic New Era of X-Plane Research
https://www.nasa.gov/aero/nasa-moves...plane-research

The first leg of the stool – computational capabilities that, in this case,
show sound produced by air around jet engine rotors that would turn in opposite directions.
Credits: NASA / Tim Sandstrom

[kach22i]

Nov. 30, 2012
Common Research Wind Tunnel Model with a Particle Image Velocimetry Plane
https://www.nasa.gov/centers/ames/or...1600-1200.html

To obtain aerodynamic and flow visualization data on a generic transport model to assess the performance of computational fluid dynamics (CFD) codes used throughout the aerospace community.

I'm just not seeing it.

Perhaps the visualization is too rapid and meant for photo sensors and not the human eye, or at least the eye of a traditional digital camera (or what ever they used here)?

[freebeard]

Amazing Mirror Experiment Reveals Invisible Air Movement!

https://www.youtube.com/watch?v=NmS6h_fkPgk

From the comments:

Hotmedal1 week ago
You need a concave mirror and a light source next to the camera aimed at the mirror. Find the focal point of the mirror and put the razor there and the camera just behind it. Then focus the camera.