"Anemometer Calibrations and Aerodynamic
Experiments to BS1042"
The Open Jet Wind Tunnel has been developed for the rapid and accurate
calibration of anemometers over the range 0.01 to 30 metre/s, and is ideal
for organisations such as 'test and calibration establishments' who regularly
check anemometers. The equipment also has uses for a variety of small scale
aerodynamic experiments where the expense and complexity of an enclosed
section wind tunnel would not be justified.
- The Open Jet Wind Tunnel consists of a single inlet centrifugal fan,
driven by 1.5 kW, 3000 rpm (max.), 0-180v D.C. continuously rated, drip-proof,
foot-mounted motor controlled by a solid-state, variable speed controller
operating on 220/240 volts, single phase, 50/60 Hz supply.
- The fan feeds air into a 200 mm diameter orifice meter, (to BS1042),
fitted with a quick action clamp for changing orifice plates. Four orifice
plates are supplied with the equipment, covering the velocity range 0.2
to 30 metres/s.
- Following the orifice meter is a smoothing chamber containing perforated
screens to provide an even flow into a final contraction section. This
is terminated with a sharp-edged exit nozzle through which the air is delivered
at test velocity. The velocity profile across any traverse is sensibly
flat with a sharp cut off at the boundary, providing a free air stream
150 mm (6 in) diameter. The outlet velocity can be periodically checked
using a pitot static tube or a calibrated test anemometer (optional).
- The instrument under test and the check instruments are mounted on
a Three-Position rotatable turret with positive locations so that each
position can be immediately centralised in the air stream.
- A 4 mm ellipsoidal nose pitot tube (supplied) is fitted at one station,
a master anemometer may be used at another station and the remaining station
holds the anemometer under test.
ACCESSORIES
Refer to Anemometer and Electronic/Test Manometer sections for complimentary
instrumentation
We suggest the AV6 Anemometer/Logger and MEDM
5K Micromanometer.