The WT278 windtunnel was built at the University of Eindhoven in the Netherlands (Contact: Prof. Dr. Bert Blocken). The wind tunnel is characterized by a large measuring chamber, the expanding corners as well as the long diffuser and the low level of turbulence.
- Measurement cross-section 2×3 meters
- Measuring length 27 meters
- Low level of turbulence
The WT278 consists of a steel profile welded construction and galvanized sheet metal. Large manholes in all relevant segments make it easy to enter the inside of the wind tunnel.
The WT278 is driven by four vibration-decoupled axial fans. The fans, which are mounted on spring shock absorbers, are connected to the wind tunnel via canvas flanges. This ensures low-noise plant operation. The nanzelle and the vanes are matched to the fans in order to generate a flow with reduced swirl.
The long diffuser, whose small opening angle counteracts flow separation, opens into the expanding large corners. The wind tunnel has a large sieve chamber. This contains four sieves at an optimal distance from one another. These non-split stainless steel sieves are accessible via manholes for easy cleaning. A honeycomb straightener with a length-to-diameter ratio of 8: 1 further reduces the swirl of the flow. In a nozzle, the nozzle geometry of which corresponds to a polynomial of the fifth order, the flow is prepared and any turbulence that may be present is suppressed.
The measurement in the wind tunnel takes place in the 27 meter long test section with a cross section of 2×3 meters. The test section consists of 9 segments with a length of 3 meters each. Each segment is equipped with a side window and a top window. The segment sides can be lifted by an electric lever mechanism for optimal accessibility. The segments can be moved out of the test section individually, which means that the previously closed test section can be converted into an open test section.
At the end of the test section there is an electrically driven turntable with a diameter of 2.5 meters. Downstream there is a sandbox and a filter rack for erosion tests. This enables erosion tests with real sand in the wind tunnel without the need for costly cleaning work. The WT278 is equipped with three traversing devices. The top traverse is located above the test section segments. This enables measurements through the top pane over the entire measuring range of 27 meters. The ground traverse is located under the test section. This allows segment-by-segment examinations to be carried out on a transparent turntable. Furthermore there is a side traversal on the side of the testsection. This carries the LDA system (laser Doppler anemometry) and can be moved over the entire 27 meters length of the test section using a rail system. A wind tunnel scale with a capacity of 2 tons is mounted directly behind the nozzle. This lowerable scale can be driven over directly and is then lifted hydraulically into the wind tunnel.