3.2 Special Purpose Wind Tunnels
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the SBS is able to generate large super cool drops and reproduce the freezing drizzle. For conventional aerodynamic tests, the spray module is replaced by a module
containing three filters to achieve low turbulence intensities. A distinguished feature
of icing wind tunnels is the need to ensure continued operation and maintenance of
measuring instruments that determine cloud conditions. Reducing the uncertainty
of these measurements and improving the process of cloud generation represent the
two main areas of scientific and technological developments in icing wind tunnels.
3.2.4 Anechoic Chambers and Aeroacoustic Wind Tunnels
The BETI (Bruit-Environment-Transport-Engineering) anechoic wind tunnel at
the PPRIME Institute in Poitiers, commissioned in 2013, is located in the premises of
the University of Poitiers on the site of the Ecole Nationale Supérieure d’Ingénieurs de
Poitiers (ENSI-Poitiers). It is a free-flow Eiffel type wind tunnel with a 90 m
3 plenum
acoustically treated to reproduce free field conditions from 200 Hz (see Fig. 3.31).
It allows the study and optimisation of the flow around obstacles and associated
acoustic radiation. Its main characteristics are as follows: open-jet test section of 0.7
× 0.7 m
2 cross section and 1.5 m length, contraction ratio of 9, maximum speed of
60 m/s (216 km/h) and turbulence intensity less than 0.5%.
The BETI wind tunnel is equipped with various measuring systems: 3-axis traverse
system and rotary table for the incidence of models, data acquisition system with up
to 64 channels, 64 microphones, antenna system for the measurement of wall pressure
fluctuations and velocity field measurement systems by hot wire anemometry, LDV
or PIV. These devices allow the identification, analysis and control of noise sources
(see Fig. 3.32). This facility is used for the aeroacoustic optimisation of elements
or parts of ground vehicles, for fundamental studies related to aeronautics or for
development of measurement techniques in aeroacoustics.
Fig. 3.31 Circuit of the BETI wind tunnel at the PPRIME Institute in Poitiers (© Institut PPRIME)
73
the SBS is able to generate large super cool drops and reproduce the freezing drizzle. For conventional aerodynamic tests, the spray module is replaced by a module
containing three filters to achieve low turbulence intensities. A distinguished feature
of icing wind tunnels is the need to ensure continued operation and maintenance of
measuring instruments that determine cloud conditions. Reducing the uncertainty
of these measurements and improving the process of cloud generation represent the
two main areas of scientific and technological developments in icing wind tunnels.
3.2.4 Anechoic Chambers and Aeroacoustic Wind Tunnels
The BETI (Bruit-Environment-Transport-Engineering) anechoic wind tunnel at
the PPRIME Institute in Poitiers, commissioned in 2013, is located in the premises of
the University of Poitiers on the site of the Ecole Nationale Supérieure d’Ingénieurs de
Poitiers (ENSI-Poitiers). It is a free-flow Eiffel type wind tunnel with a 90 m
3 plenum
acoustically treated to reproduce free field conditions from 200 Hz (see Fig. 3.31).
It allows the study and optimisation of the flow around obstacles and associated
acoustic radiation. Its main characteristics are as follows: open-jet test section of 0.7
× 0.7 m
2 cross section and 1.5 m length, contraction ratio of 9, maximum speed of
60 m/s (216 km/h) and turbulence intensity less than 0.5%.
The BETI wind tunnel is equipped with various measuring systems: 3-axis traverse
system and rotary table for the incidence of models, data acquisition system with up
to 64 channels, 64 microphones, antenna system for the measurement of wall pressure
fluctuations and velocity field measurement systems by hot wire anemometry, LDV
or PIV. These devices allow the identification, analysis and control of noise sources
(see Fig. 3.32). This facility is used for the aeroacoustic optimisation of elements
or parts of ground vehicles, for fundamental studies related to aeronautics or for
development of measurement techniques in aeroacoustics.
Fig. 3.31 Circuit of the BETI wind tunnel at the PPRIME Institute in Poitiers (© Institut PPRIME)