Mars Anemometer Test and Calibration Facility
All past lander missions to Mars, and most proposed missions, have carried
anemometers to measure wind speed & direction near the surface. Oxford
Density Wind Tunnel (LDWT) is being used to create a facility in which
anemometers can be tested and calibrated in Martian surface conditions,
namely a carbon dioxide atmosphere at pressures of 5-10 mbar, temperatures
of 160-300 K, and flow speeds ranging from 0.5 m/s to 30 m/s. The
primary determination of wind speed is obtained from orifice plates
which measure the flow rate into the wind tunnel. The flow field is
characterised using a pitot tube on a translation stage. This
facility was developed for testing and calibration of a wind sensor for the
mission (2003), and may also be used to calibrate sensors for the NetLander
mission (CNES, 2007).
Test section is circular, 180mm in diameter
- Flow speeds achievable are 0.5 - 30 m/s.
(or 1-60 m/s using 120mm diameter nozzle)
- Pressure is 5 - 10 mbar.
- Gas used is CO2 or dry air.
- Airflow temperature can be set in the range 200K - 300K using the
- Absolute flowspeed accuracy is 3% of flowspeedfor all speeds > 1 m/s
- Repeatability is better than 1% of flowspeed for all speeds > 1 m/s
- Fluctuations in flowspeed are at most 0.3% of flowspeed
A publication describing the wind tunnel in this mode is:
C. F. Wilson, A.L. Camilletti, S.B. Calcutt & P.M. Ligrani, A wind
tunnel for the calibration of Mars wind sensors, Planetary and Space
Science, 2008, doi:10.1016/j.pss.2008.05.011.
A close-up of the test section can be seen here.
The design adopted is shown schematically here:
This facility has been designed in collaboration with the wind tunnel
research group in Oxford University's Department
of Engineering Science. It is located at the Osney Laboratory,
near the train station in Oxford.
Links to other
Martian Wind tunnels
For further details, please contact:
Department of Atmospheric, Oceanic, and
Oxford University, OXFORD OX1 3PU, U.K.
Tel: +44 1865 272 086
Fax: +44 1865 272 923