To improve both flow quality and test productivity, three major components of our large transonic wind tunnel are upgraded:
- Test section walls: besides the exchangeable slotted walls, a new set of perforated walls is now available. The perforated walls provide reduced blockage in the high-subsonic flow regime and improved wave cancellation characteristics at low-supersonic flow conditions.
- Model control: a brand new model control system now allows for AoA sweeping up to 1°/s. The systems ensures AoS stays within ± 0.1° bounds during AoA sweeps – and vice versa.
- Mach control: An improved Mach control system keeps Ma within ± 0.002 and ± 0.003 for sub- and supersonic conditions respectively. The controller can now keep up with the increased model sweep rates, even beyond the point where model flow separation occurs.
This upgrade is funded by the Royal Netherlands Aerospace Centre and supported by the joint R&D efforts of DNW, NLR and DLR.
The next phase is the upgrade to further enlarge the Ma-AoA envelope.