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The calm before the storm
The languid serenity that emanates from the large blue-
silver blades is deceptive. The ultra-strong aluminium
components do not touch the ground. Beneath their
mounting, they conceal a high-performance propulsion
system. Once these gigantic blades start to rotate, all
that remains is an aircraft model or component whose
aerodynamic properties need to be investigated. Sixteen
rotor blades mounted in front of the stationary stator then
propel air at a maximum speed of 325 kilometres per hour
directly onto the model.
The low-speed wind tunnel in Braunschweig is operated
by the German-Dutch consortium Deutsch-Niederländische
Windkanäle (DNW-NWB). In 2010, it obtained a new, much
quieter drive unit to enable acoustic measurements. At
the end of the wind tunnel (the golden area visible in the
background), aero-acoustically optimised profiles ensure
that air flow is carefully directed around the corner – hence
its name, ‘Umlenk-Ecken’ (deflecting corners).
Image: DLR/Heinrich (CC-BY)
Perspective
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