Mach 5 Quiet Ludwieg Tube
QLT5 was installed in May 2019 and recently completed shakedown and calibration. It currently operates as a conventional tunnel and a quiet nozzle upgrade is currently in the fabrication stage and is expected to be delivered in mid-2022. Tunnel run parameters and instrumentation are given in the tables below.
Tunnel operating parameters
| Parameter | Units | Range |
|---|---|---|
| Mach number | -/- | 5.0 |
| Quasi-steady run time | ms | 100 |
| Test-section diameter | mm (in.) | 381.0 (15.0) |
| Unit Reynolds number, Re' | 106 m-1 (106 ft-1) | 5.2–39.9 (1.6–12.2) |
| Total pressure, p01 | kPa (psia) | 344.7–2068.4 (50–300) |
| Total temperature, T01 | K (°F) | 385–450 (233–350) |
Tunnel Instrumentation
| Component | Channels | Specifications |
|---|---|---|
| NI PXIe-6378 analog-to-digital converters | 32 | 16-bit, 3.57 MS/s/ch. |
| NI PXIe-6361 analog-to-digital converter | 16 | 16-bit, 2 MS/s |
| NI PXIe-4353 thermocouple blocks | 64 | 24-bit, 90 S/s |
| Precision Filters 28144 resonant sensor excitation | 32 | ≥1 MHz bandwidth |
| Precision Filters 28612 programmable LP filter/amplifiers | 32 | fc ≤ 3 MHz |
| Kulite KSC-2 signal conditioner | 4 | Resonance compensation |
| FLIR X8501sc MWIR thermography | 1 | 14-bit, 1280×1024 px, 3.0 µm– 5.0 µm |
| Focusing schlieren (Photron FastCam SA-Z, Spectabit Optics) | 1 | up to 1024×1024 px, up to 2.1M fps (reduced res) |