3.1 Subsonic Wind Tunnels for Aeronautics
63
Fig. 3.17 Study of the model support effect in the F1 wind tunnel (© ONERA)
3.1.7 Large Research Wind Tunnels
The L2 wind tunnel of ONERA Lille centre is located in an industrial hall of
725 m
2 forming the return circuit. The test section, guided over a length of 13 m, has
a rectangular section, 6 m wide and 2.4 m high. The settling chamber is equipped
with a honeycomb which was added in 2015. A diffuser leads to motor-fans equipped
with individual diffusers. The displacement of the probes is achieved by a sufficiently
precise 3 axes motorised gantry suspended from the ceiling. On the floor, a 6 m
diameter turntable helps in positioning the models accordingly to a desired angle
with respect to the wind direction. The flow in the test section is generated by a set
of 18 motor-fans mounted in 3 rows over a height of 2.8 m, with a total power of
125 kW (see Fig. 3.18). A maximum velocity of 19 m/s can be achieved in the empty
test section.
The L2 wind tunnel is well suited to study the effects of wind on land or on the
sea, thanks to the ability to simulate the atmospheric boundary layer (average speed
profile). The air flow development over aircraft carriers has been studied in this wind
tunnel in order to characterise and mitigate various phenomena such as turbulent
levels in the landing zones, soot fallout, studies of smoke plumes for pilot visibility
63
Fig. 3.17 Study of the model support effect in the F1 wind tunnel (© ONERA)
3.1.7 Large Research Wind Tunnels
The L2 wind tunnel of ONERA Lille centre is located in an industrial hall of
725 m
2 forming the return circuit. The test section, guided over a length of 13 m, has
a rectangular section, 6 m wide and 2.4 m high. The settling chamber is equipped
with a honeycomb which was added in 2015. A diffuser leads to motor-fans equipped
with individual diffusers. The displacement of the probes is achieved by a sufficiently
precise 3 axes motorised gantry suspended from the ceiling. On the floor, a 6 m
diameter turntable helps in positioning the models accordingly to a desired angle
with respect to the wind direction. The flow in the test section is generated by a set
of 18 motor-fans mounted in 3 rows over a height of 2.8 m, with a total power of
125 kW (see Fig. 3.18). A maximum velocity of 19 m/s can be achieved in the empty
test section.
The L2 wind tunnel is well suited to study the effects of wind on land or on the
sea, thanks to the ability to simulate the atmospheric boundary layer (average speed
profile). The air flow development over aircraft carriers has been studied in this wind
tunnel in order to characterise and mitigate various phenomena such as turbulent
levels in the landing zones, soot fallout, studies of smoke plumes for pilot visibility