Luminous Landscape Forum
The Art of Photography => The Coffee Corner => Topic started by: Matt Tilghman on May 15, 2014, 01:39:10 pm
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Hey all. I hope this goes here... I couldn't really find another board that fit it perfectly, so I decided this one seemed appropriate. Let me know if you think there's a place it would fit better.
I work in a combustion lab, specifically Stanford's High Temperature Gasdynamics Lab. Like most research, it's nowhere near as glamorous as people might think, and definitely not as glamorous as this video would seem to hint. But we do have lots of cool tools and diagnostics, and sometimes get the chance to play around with them. There's an upcoming "Art of Science" exhibition, and we thought it would be cool to create something using one of my friend's high-speed cameras. We ultimately decided to film a match tip using a technique called Schlieren Imaging, which visualizes the derivative of fluid density. I thought it was really fascinating, and thought you guys might enjoy it too. Here is the video, and below is the caption for the exhibition.
https://www.youtube.com/watch?v=a8PTlGWXarI (https://www.youtube.com/watch?v=a8PTlGWXarI)
(is there a way to embed this?)
Here is a still teaser:
(http://matttilghman.com/images/Schlieren%20Match.jpg)
"A strike-anywhere match is lit and unsuccessfully extinguished in this video.
We use schlieren imaging to visualize the flow. Schlieren is a technique originally used in the 19th century to detect defects in optical lenses that is exquisitely sensitive to changes in fluid density
In the beginning of the video, a match is struck against its box, generating heat via friction that prompts a reaction between chemicals in the match head. As these chemicals react, they produce hot gases, which jet out and away from the match. The reactions progress until eventually the match is lit, and hot combustion products rise rhythmically upward.
To extinguish the fire, a character enters from the right to blow out the flame. When the jet of exhaled air reaches the match, the frame rate increases to from 2,000 frames per second to 10,000 to capture the incredibly complex and rich turbulent structure that arises from the breath interacting with the flame. Even in the storm of the turbulence, the jet of exhaled air fails to mix enough cool air into the flame to extinguish the persisting solid reactions, and the match eventually reignites.
All this happens in just 1.5 seconds."
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Interesting. Thanks,
Alan
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Wow. Fascinating.
Jeremy
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Great! Thanks for posting.
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Super cool Matt! Thanks for posting.
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Way cool Matt, way cool.
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Instructive, spectacular and beautiful. Thanks for sharing.
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I'll never again view a match as a "simple" thing. Wow!
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Thanks all!
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It's about time; it's about space. Very cool indeed.
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Wow indeed!