Brocken, the highest mountain in Northern Germany (1143 m), is famous for its harsh climate and represents a rigorous test environment for wind sensors.
Our new sonic versions were operated here successfully in winter 2011/2012. The main change with regard to former models is the replacement of brazen material by stainless steel. Due to the limited thermal conductivity of stainless steel the implementation of an efficient and sufficient heating power turned out to be a challenge and called for verification in field tests.
The figures show the uSonic-2 Heavy Duty and the uSonic-3 Scientific with extended heating mounted on the roof of the LUESA1 observation station during an extreme icing event. While the ice incrustation reached more 50 cm thickness at the supporting structures, the sensor heads remained completely ice free thus providing unaffected operational measurements.
Beside of the icing events Brocken is famous for frequent high wind speeds which during this winter time reached up to 35 m/s. Both, the uSonic-2 and the uSonic-3, are capable to measure wind speeds of more than 60 m/s, and the combination of high wind speeds on one hand and the and heavy icing on the other represents the adequate challenge to prove reliability and hardness in harsh conditions of the uSonic sensors.
1LUESA = Luftueberwachungssystem Sachsen Anhalt