S4MA
Hypersonic, Blow down wind tunnel, Ø 0.68 to 1 m nozzles
The Modane S4 wind tunnel produces an airflow at a maximum stagnation pressure of 120 bar and a maximum stagnation temperature of 1,800 K (see the operating range).
Axisymetric nozzles, Mach 6.4; 10 and 12
Run duration up to 90 seconds (with 8,000 m3 vacuum downstream tank at 10 mbar).
- Compressed air: 270 bar, 29 m3 upstream storage tanks, repressurized by a 5.7 kg/s mass airflow compressor.
- Vacuum: 0.010 bar minimum pressure, 4,000 or 8,000 m3 storage tanks, sucking in air at up to 15 m3/s.
INSTRUMENTATION AND MEASUREMENT METHODS
- Data acquisition system with 48 to 72 analog channels, and possible extension up to
- 120 channels by adding simplified channels for thermal measurements.
- Steady measurement rate up to 25 Hz per channel with a 14-bit A/D converter.
- Unsteady measurement rate up to 100 kHz per channel (80 channels).
- Pressure measurement by individual transducers or PSI® electro-pressure scanner: rate can reach 1,472 mean values every 10 seconds (the average value is calculated from a sample of 127 results per channel).
- Temperature measurement by thermocouples infrared thermography, on thermo sensitive paints.
- Force measurement by ONERA 6-components balances; numerous balances available and new ones manufactured on request; hinge moment measurement by appropriate balances.
- Flow visualization by steady or spark shadowgraph (800 mm field diameter), colored oils, thermosensitive paints, infrared.
- Laser velocimetry on request.
- Portable data acquisition and processing system designed to support off-line model preparation.
TEST SECTIONS
| Nozzle | Mach 6.4 | Mach 10 | Mach 12 |
| Outlet diameter | 0.685 m | 0.994 m | 0.994 m |
| Throat diameter | 75.43 mm | 36.61 mm | 21.53 mm |
| Maximum Reynolds number(L=1m) | 28 million | 7.8 million | 3.2 million |
| Run time (standard conditions) | 40 to 90 seconds | 25 to 85 seconds | 25 to 85 seconds |
| Runs per 8-hour day | 5 | 5 | 4 |
TYPICAL TESTS
- Force measurements (6 components) on complete models.
- Force and hinge moment measurements on model elements and control surfaces.
- Wall pressure measurements, air intake probes (pressure, flow angularities).
- Thermal flux measurements (on complete models or model elements).
- Mechanical or thermal testing of real elements (e.g. coating).
- Ramjet tests with hot air feed.


