The VKI H-3 tunnel is a blow-down facility designed to generate hypersonic flows at large Reynolds numbers. It is currently equipped with an axisymmetric nozzle yielding a uniform Mach 6 free jet with a core flow diameter of 120mm. Wind tunnel operational capabilities are being broadened with the addition of a new Mach 5 contoured nozzle.
Dry air is supplied from a pebble-bed heater at stagnation pressures from 7 to 35 bar and a maximum stagnation temperature of 550 K. The free-stream unit Reynolds number may be varied from 3×10^6 to 30×10^6/m with the existing Mach 6 nozzle, and is anticipated to reach up to 65×10^6/m with the new Mach 5 nozzle.
The test section is equipped with a high-accuracy five-degree-of freedom orientation mechanism and a rapid injection mechanism that enables model injection into the hypersonic stream in less than 0.1s. Typical useful test times extend up to 30s. A modern data acquisition architecture is composed of a National Instrument data acquisition system. Advanced instrumentation is available for both localised (thermocouples, pressure sensors) and global measurement techniques (Infra-Red, 3-components balances). Additional measurement techniques may be used for specific needs. The tunnel is also equipped with high-quality shadowgraph and schlieren optical systems.
• Blow down hypersonic wind tunnel
• Reservoir pressure from 0.7MPa to 3.5MPa
• Reservoir temperature of 550K
• Mach 6 contoured nozzle (with a core diameter of 120mm)
• Mach 5 contoured nozzle (with a core diameter of 120mm)
• Reynolds number from 3 to 30 millions/m
• Test times up to 30 s
• 5-axes positioning mechanism
• IR camera
• 3-components balances
• Piezoelectric pressure sensors
• Flow visualization techniques (Shadowgraph/Schlieren) coupled with a high-speed camera.