BMI has designed and constructed a wind tunnel facility for characterization
of velocity and turbulence fields inside of and surrounding devices requiring
specified aerodynamic performance. The wind tunnel is capable of generating
120 m/s wind speeds inside an 8” cylindrical test section. It is
instrumented with redundant pressure and temperature measurements and
has translatable stages for four hot wire or hot film anemometers to
allow radial profile measurements to be made of velocity and turbulence
inside or outside of devices mounted inside the test section.
The wind
tunnel has a data acquisition system typically operated at a sampling
rate of 1000 Hz and data processing software for rapid visualization
of experimental results. One application of the wind tunnel has been
to characterization the fluid flow inside diffuser cones used to sample
air pollutants from research aircraft. Contingent on funding suppor
BMI plans to integrate particle generation and detection instrumentation
into the wind tunnel so quantitative sampling efficiency studies may
be performed on devices mounted inside the tunnel. BMI is interested
in working together with customers requiring wind tunnel testing of their
devices.
To characterize the wind tunnel performance, radial and axial
velocity and turbulence profiles have been measured using hot wire anemometers
(Dantec Dynamics 55P16). Profile measurements indicate velocities between
98 and 104 m/s within a +/-3.25” radial distance of the test section center
and turbulence intensities between 2 and 4% for the same radial
distances. The test section has a 4” radius. Plots of the radial
profiles are provided and the solid dots on the plots indicate +/- one
standard deviation in the respective measurement. BMI is interested in
working together with customers requiring wind tunnel testing of their
devices.
Performance Characterization
