COST 727 Action. COST: European Cooperation in Science and Technology. Measuring and forecasting atmospheric icing on structures. Alain Heimo Meteotest, Switzerland MC Chairman/COST727.
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COST: European Cooperation in Science and Technology
Measuring and forecasting atmospheric icing on structures
COST is one of the longest-running instruments supporting co-operation among scientists and researchers across Europe.
Atmospheric icing causes severe financial losses and reduces security and human safety :
- Power line transmission …
On TV-towers the ice load may
be several tens
WMO/CIMO Wind Instrument Intercomparison
Mont Aigoual, France, 1992-1993
Organized by France, Switzerland & WMO
Participating countries: 11
Instruments tested: 26
EUMETNET SWS-II (2000-2003)
Acquisition of meteorological data under icing conditions in Finland (Luosto), France (Mt. Aigoual) and Switzerland (Säntis)
Measurement period: 1.10.2001 to 30.4.2002
Conclusions and recommendations:
- …. Already during the installation and test period proceeding the experiment, it was quickly recognized that the lack of adequate instruments for the characterization of ice accretion would represent a serious drawback for the whole experiment.
- … it is important thatmore care is given within the meteorological community to produce accurate measurements under harsh conditions and to promote measurements of icing.
Non-COST Participant: Japan (Kanagawa Institute of Technology)
in Cryospheric Environment Simulator at
Shinjo Branch of
National Research Institute for Earth Science
and Disaster Prevention
in Kanagawa Institute of Technology
< 20m/s (with a larger test section)
< 100m/s (in a smaller test section)
> -25 deg. Cel.
< 20m/s (1m by 1m test section)
> -25 deg. Cel.
Sprayers not installed all the time
Czech Republic (Studnice)
Deadwater Fell, UK
Following the ISO12494 standard (Atmospheric icing of structures), the in-cloud ice accretion on a cylinder can be expressed by the formula:
a1 = Collision efficiency
a2 = Sticking efficiency
a3 = Accretion efficiency
w = Mass concentration of cloud water (LWC)
A = Cross sectional area
V = Wind speed
Test simulations have been carried out with the weather model WRF extended with the above algorithm.
Data acquisition failure
Ice load and strong winds -> tower collapse
Activitiesuntil end of Action
The Final Workshop of COST-727 Action
13th International Workshop on Atmospheric Icing on Structures IWAIS
will be held jointly in Andermatt (Switzerland) , 8-11.9.2009
Please register at: www.IWAIS2009.ch
Thank you for your attention !