IIHR's
2-D video disdrometer was purchased with NSF support from Joanneum
Research, Graz, Austria. The original disdrometer experienced some
temperature-related problems during a NASA/TRMM field campaign, and IIHR
personnel subsequently enhanced the disdrometer by combining the
different units in an air-conditioned housing and by adding software for
synchronizing data collection. For a picture of the original
configuration, please refer to the manufacturer's website (www.disdrometer.at).
 |
| Construction
of the 2-D video disdrometer. For clarity only one light sheet
and one camera is shown. |
|
 |
| 2-D
Video disdrometer deployed in Brazil as part of a NASA TRMM
field campaign. |
The 2-D video disdrometer
principle of operation. Two orthogonal light sheets that are projected
onto line-scan cameras form the virtual measuring area. Hydrometeors
that fall through the light sheet cast a shadow that is recorded by the
cameras (this is analogous to flat-bed scanners, except here the scan
head is stationary and the scanned object moves). Detailed shape and
size information for each individual hydrometeor is available. The light
sheets are spaced 6 mm apart; this is used to measure the vertical fall
velocity.
More Information
For more information
about the IIHR 2-D video disdrometer contact Dr.
Anton Kruger or Prof.
Witold Krajewski.
See also 2D-Video Disdrometer Workshop |
