Timeline for What do the components of a shockwave's visual artefacts represent?
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 1, 2017 at 8:00 | answer | added | xxavier | timeline score: 2 | |
| Jun 15, 2016 at 9:54 | history | tweeted | twitter.com/StackAviation/status/743018776329916416 | ||
| Jun 14, 2016 at 3:02 | review | Close votes | |||
| Jun 14, 2016 at 4:21 | |||||
| Jun 6, 2016 at 17:38 | comment | added | mins | ... About shadow creation: Can air make shadows? --- and Why do the edges of glass blocks create a shadow?. See also Schlieren imaging pointed by @ROIMaison (video) | |
| Jun 6, 2016 at 17:23 | comment | added | mins | The wing is illuminated 1/ By the scattered ambient light; 2/ By the ambient light altered when crossing the shockwave refractive volume: Refraction creates a shadow more or less visible by diverting a part of the light elsewhere; 3/ The direct light from the Sun (if any) which creates another (stronger) shadow. Then you see this illuminated wing through the shockwave. The rays are again curved / folded by the index changes, so the portion of the wing may not match exactly the surrounding details (that's not visible on the image)... | |
| Jun 6, 2016 at 16:52 | comment | added | Daniele Procida | @mins It's not clear from your answer whether what I am seeing is the wing, with a narrow line of distortion in the image caused by the change in refractive index, or a shadowgram of that refractive distortion projected onto the wing by the (nearly) overhead sun. | |
| Jun 6, 2016 at 7:39 | comment | added | ROIMaison | This phenomenon is actually often used to visualize shocks in wind tunnels and experiments, see Schlieren photography And since we have an 'aerodynamics' tag, I don't think this is off-topic. | |
| Jun 6, 2016 at 7:21 | review | Close votes | |||
| Jun 6, 2016 at 11:43 | |||||
| Jun 6, 2016 at 7:06 | comment | added | mins | Related (not a duplicate): Is the visual artifact seen over the wing from different air densities, a reflection or something else? | |
| Jun 6, 2016 at 6:33 | comment | added | Federico | I'm not sure this question is about aviation, also given @mins' comment above. | |
| Jun 6, 2016 at 6:06 | history | edited | sweber | CC BY-SA 3.0 |
Added picture with increased contrast, since original doesn't show it very well
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| Jun 6, 2016 at 5:59 | comment | added | mins | You see a mirage, that is an image deformed by the change of refractive index, due to the huge change in air pressure / temperature / density. See shadowgraph. As the index changes, the phase of the light is altered, creating interferometric shadows. You can compare this with the effect visible over a hot road surface. | |
| Jun 6, 2016 at 2:10 | history | asked | Daniele Procida | CC BY-SA 3.0 |
