The new low speed wind tunnel of the TU Braunschweig

The low speed model wind tunnel (MUB) has been transferred from the DNW-NWB to the Institute of Fluid mechanics of the TU Braunschweig (ISM). The wind tunnel is a closed return atmospheric wind tunnel with three different test sections. Two of them are closed and one is an open test section. The wind tunnel has been improved by a new closed test section with a cross section of 1.3×1.3 m. A maximum speed of 60 m/s is achieved with this test section. The second closed test section has a cross section of 0.8×0.8 m which allows velocities up to 140 m/s. Another option is an open test section with a jet that measures 1.3 m. The maximum Reynolds-Number is 7.5*10⁵. The major improvement is the addition of a heat exchanger, which allows to keep the temperature of the flow constant. As a research facility the tunnel incorporates extensive flow measurement instrumentation including probe traversing and particle image velocimetry (PIV) systems. The new test section allows optimal and flexible optical access as well as the usage of conventional measurement technique.