|
IARD article in Proceedings of SPIE, Defense&Security Symposium (March, 2008) |
Dew, dust, and wind
influencing thermal signatures of objects. Arcady Reinov, Yossi Bushlin, Alex Lessin, Dieter
Clement, Proceedings of SPIE Vol. 6941, 6941 - 29, 16 – 20 March 2008,
Orlando, Florida, USA. |
abstract Dew and dust layers on the
surface of an object may significantly affect its thermal state and IR signature.
Dew formation begins when the object surface temperature falls below
atmospheric dew point temperature. Due to the latent heat released by the
water accumulated on the surface the temperature drop stagnates and the
object appears warmer then it would be without dew formation. An attempt was
made to modify RadThermIR software to account for dew effects. A simple plate
model and the more elaborate CUBI thermal modeling benchmarking object were
used to study the extent to which dew may change thermal object signatures. A
dust layer on an object surface may affect its optical properties and may act
as additional thermal insulation when it is thick enough. Both effects
influence the temperature and IR signature of the object. Parametric
calculations by RadThermIR were performed for various dust thicknesses and
optical properties. This data was used in an object/background contrast
analysis. The obtained dust/dew layer results will be used in the planning of
the next CUBI experiment in natural desert environments. In addition, CUBI
data from another geographic location was used for studying different wind
models resulting in some interesting conclusions concerning the applicability
of the wind model used in RadThermIR |