106
4 Transonic Wind Tunnels
4.3.2 Transonic Wind Tunnel for Research
The S3Ch wind tunnel at the ONERA Meudon centre is a research wind tunnel
whose dimensions are appropriate to the studies of part configurations such as wing
profiles, after-bodies, wing-nacelle sets, etc. Its Mach number range extends from
0.3 to 1.2. Its total pressure is close to the atmospheric pressure and total temperature
being in the range of 290–330 K. The average turbulence intensity in the upstream
part of the working section is 0.15%.
The tunnel is operated by a two-stage power unit with a power of 3.5 MW and a
compression ratio of 1.25. The test section shown in Fig. 4.11 has a rectangular cross
section of 0.76 × 0.80 m
2 and a length of 2.2 m. It can be equipped with rigid top and
bottom walls, perforated, or with deformable and adaptive walls (see Sect. 4.2.2),
which makes it a unique facility. The side walls include optical grade windows for
optical flow diagnostics. The wind tunnel is equipped with an axial model support
with internal balances allowing a variation of incidence angles or sideslip angles of
60°, without significant displacement of the model from the centre of the test section.
It is possible to mount the models on the wall of the test section with external or
internal balance and variable incidence over 360°. A compressed air supply at a
rate of 2 kg/s, under a pressure of 40 bar and a temperature of 300 K can simulate
propulsion jets or supply a TPS (see Fig. 4.12). The wind tunnel also has a 90 kW
heater, to provide hot air flow at a rate of 0.5 kg/s, to simulate a propulsion jet at a
temperature of 600 K.
The wind tunnel allows implementation of flow diagnosis techniques for steady
and unsteady pressure measurements using PSP and PIV, two- and three-components
LDV for measurement of the velocity field, as well as various visualisation methods.
It is also widely used for laminar to turbulent transition control studies.
Fig. 4.11 Circuit of the S3Ch transonic wind tunnel at ONERA, Meudon (© ONERA)
4 Transonic Wind Tunnels
4.3.2 Transonic Wind Tunnel for Research
The S3Ch wind tunnel at the ONERA Meudon centre is a research wind tunnel
whose dimensions are appropriate to the studies of part configurations such as wing
profiles, after-bodies, wing-nacelle sets, etc. Its Mach number range extends from
0.3 to 1.2. Its total pressure is close to the atmospheric pressure and total temperature
being in the range of 290–330 K. The average turbulence intensity in the upstream
part of the working section is 0.15%.
The tunnel is operated by a two-stage power unit with a power of 3.5 MW and a
compression ratio of 1.25. The test section shown in Fig. 4.11 has a rectangular cross
section of 0.76 × 0.80 m
2 and a length of 2.2 m. It can be equipped with rigid top and
bottom walls, perforated, or with deformable and adaptive walls (see Sect. 4.2.2),
which makes it a unique facility. The side walls include optical grade windows for
optical flow diagnostics. The wind tunnel is equipped with an axial model support
with internal balances allowing a variation of incidence angles or sideslip angles of
60°, without significant displacement of the model from the centre of the test section.
It is possible to mount the models on the wall of the test section with external or
internal balance and variable incidence over 360°. A compressed air supply at a
rate of 2 kg/s, under a pressure of 40 bar and a temperature of 300 K can simulate
propulsion jets or supply a TPS (see Fig. 4.12). The wind tunnel also has a 90 kW
heater, to provide hot air flow at a rate of 0.5 kg/s, to simulate a propulsion jet at a
temperature of 600 K.
The wind tunnel allows implementation of flow diagnosis techniques for steady
and unsteady pressure measurements using PSP and PIV, two- and three-components
LDV for measurement of the velocity field, as well as various visualisation methods.
It is also widely used for laminar to turbulent transition control studies.
Fig. 4.11 Circuit of the S3Ch transonic wind tunnel at ONERA, Meudon (© ONERA)