| Category | Description |
|---|---|
| Responsible | Stephan Sattler |
| Test Section Size | 1 m x 1 m x 6 m |
| Max. Velocity | 6 m/s |
| Max. Re | 2.5 x 10⁶ |
| Motor power | 160 kW |
| Turbulence | < 0.2% |
| Max. Pressure against atmosphere | 2 bar |
| Max. Temperature | 40 °C |
The GWB is a Göttingen-type water tunnel that enables fully time-resolved measurements at moderate Reynolds numbers, employing both pressure measurement techniques and spatially resolved optical methods. Because water’s kinematic viscosity is substantially lower than that of air, high Reynolds numbers can be achieved even at moderate flow velocities. The low flow velocity is a major advantage for precise time-resolved field-measuring techniques (especially PIV) at these high Reynolds numbers. Heating the water to up to 40 °C further reduces its viscosity, allowing even higher Reynolds numbers and thus a considerably larger portion of the flow dynamics seen in air at similar Reynolds numbers to be captured in the water tunnel.
The test section has a quadratic cross-section with a length of 6 m, allowing tests of objects up to about 0.5 m in length. The test section is constructed entirely of stainless steel. The main frame comprises interchangeable wall segments. In the standard configuration, one-third of these segments are made of safety glass, enabling optical measurement techniques—especially PIV. One of the side-wall windows is designed as door for easy access to the test section.