Wind tunnel for large systems

The German Wind Guard Engineering GmbH, Varel has now improved its large acoustic wind tunnel. This makes it possible to achieve flow rates of 100 meters per second. Profile investigation on rotor blades can now be carried out at Reynolds numbers of more than six million.

Manufacturer of wind turbines use the wind tunnel in Bremerhaven, the acoustic and aerodynamic properties of components or models - especially ahead of rotor blades - check. The Reynolds number is important for the model tests to reliably transferred to real proportions. Since wind turbines are getting bigger, so must the Reynolds number corresponding to "grow" so that the flow conditions can be applied to models of the real turbine. "At high Reynolds numbers of six million tests for the accurate rotor blade development for both the onshore and are also available for the offshore sector," says Knud Rehfeldt now, managing director of the German Wind Guard. Previously, the value was in the wind tunnel at around four million Reynolds.

The acoustically optimized large wind tunnel in Bremerhaven is already the fourth largest wind tunnel, and the German Wind Guard. "The wind tunnel has very high wind speeds at low turbulence and low noise emission," said Wind Guard spokeswoman Cornelia Jäger. However, it was in Bremerhaven has not reached the capacity limits. They wanted to optimize the flow channel further and bring the Reynolds number even further upward. "The trick is that the flow remains homogeneous," says Hunter. Here are some research work to be done.

The optimization of the wind tunnel was part of the project "ReynoldsWK" instead, which ran from April 2010 to September 2011. It has received € 127,577 from the Bremerhaven Society for Urban Development and Investment Promotion Ltd. (BIS) as part of the environmental support of the Bremen Senator for Environment, Construction and Transport, with funding from the European Regional Development Fund (ERDF).