View Single Post
Old 05-15-2022, 12:42 PM   #7 (permalink)
Master EcoModder
freebeard's Avatar
Join Date: Aug 2012
Location: northwest of normal
Posts: 23,841
Thanks: 6,735
Thanked 7,620 Times in 6,222 Posts
Why have you never mentioned it before?
LED lamps of a specific wavelength are used to excite the pressure-sensitive probe within the paint. Once excited, the pressure-sensitive probe is transitioned to a higher energy state where it may either emit a photon or be quenched by local oxygen present. This competing process of emission and quenching determines the intensity response of the paint layer. The result is a dimmer fluorescence where there is higher pressure and brighter response at lower pressures.

The intensity emitted from the surface is then recorded through a long-pass filter by a CCD or scientific grade camera and stored for conversion to pressure using a previously determined calibration. Images of the paint layer are recorded at three conditions. A wind-off image at a known reference condition which is typically standard atmospheric conditions with the tunnel turned off. A wind-on image at a loaded condition where the wind tunnel is running at condition. And lastly a background image where the ambient light present is captured without the illumination source. The background image is then subtracted from the wind-off reference and the wind-on condition image in data processing.

Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster

"History has stopped. Nothing exists except an endless present in which the Party is always right." G. Orwell

  Reply With Quote