A
Hot-Wire anemometer is an instrument for measuring fluid velocity, whether it
be of gases or fluids, hot wire or hot film, Hot-Wire Anemometers measure fluid
speed using a delicate probe made of thin tungsten/platinum wire, or a thin
metallic film. This probe is heated to a temperature higher than average temperature
of the fluid. Using sophisticated circuitry, the anemometer stabilizes and maintains
the probe temperature at a constant level throughout the measurement. Since
the fluid flowing past the probe has a lower temperature than the probe, the
film/wire is constantly being cooled by the fluid flow. The higher the velocity,
the faster the rate of cooling.
Since the anemometer must maintain the probe temperature at a constant level,
it is therefore sensitive to the rate at which it is being cooled, i.e., the
fluid velocity. This velocity is translated to a continuously changing voltage
which has a nonlinear relationship with the flowing fluid. This voltage then
undergoes signal conditioning, to filter out noise and improve the Signal/Noise
ratio.
After proper calibration of the probe channels, it is possible to measure fluid
velocities with an accuracy of 0.05% or greater, depending upon the measurement
range and the quality of the calibration. The response time between measurement
and instrument output is very short in comparison with other methods of fluid
flow measurement and can reach a minimum of 1/2 microsecond.
The AN-1003 Anemometry system measures at that speed up to 10 channels simultaneously!
Easy
operation.
Low Noise - less than 2.2 nV/. Ultra Low Noise option - less than 400pV/.
Intelligent modular design.
CTA and CCA in a single channel (optional).
Probe protection circuit.
Soft-start circuit for delicate probes.
High frequency response: DC-100kHz standard, DC-500kHz optional.
Flexible: may be used with Hot-film and Hot-wire.
Built-in Signal Conditioner :
- Controllable Gain,
- DC offset, adjustable to any value,
- Noise Filter: Low Pass Filter with 12 cut-off frequencies.
Built-in indicators aid user in balancing the Bridge.
Built-in Square Wave/Pulse Generator.
Fail-safe switches.
Self-maintained, no expensive servicing required.
12-months Parts & Labor warranty.
The
AN-1003 Hot-Wire Anemometer can measure fluid velocities from 0 and up to supersonic
speeds. In addition to these inherent qualities of the basic AN-1003 system,
there are 14 extra options
which can be added to any number of channels. These expand the capabilities
of the system, allowing it to make professional-standard measurements in different
kinds of fluids.
Another advantage of the AN-1003 is its modularity: channels can be removed
or interchanged without disturbing other channels already calibrated for different
experiments.
The AN-1003 is being used today at a large number of leading research institutes
and universities throughout the world, where, for a number of years, it has
proved its value as a reliable and accurate instrument, and has become a valuable
research tool for scientists and engineers. Part of the AN-1003's success is
due to its user-oriented design, making the system easy and straightforward
to use by inexperienced students and professional researchers alike. We hope
that you become part of this expanding group of satisfied AN-1003 users.
Refer to the Technical
Specificationto find out about the outstanding
capabilities and characteristics of the AN-1003. As a result of technological
advances in design and production, A.A. Lab Systems can now offer you a complete
AN-1003 anemometry system at a substantially lower price than in the past, making
this highly reliable and accurate system highly affordable as well.
Call or e-mail
for any information you need that is not covered in this Web Site - our professional
staff will be happy to answer any technical questions you may have.
Option
01 -
ULTRA
LOW NOISE INPUT AMPLIFIER - 400 PicoVolts /
- less than 0.1mVrms output noise on 0-20kHz bandwidth. Option 03 -
TEMP. COMPENSATION - discontinued, use Option 11 instead. Option 04 -
FREQUENCY COMPENSATION - a tunable circuit for improving the frequency response
up to 500kHz. Option 05 -
BACKUP BATTERIES - provides operation without mains current for more than 2
hours. Built-in charger included. Option 06 -
FILTER BANDS - other than specified. Please specify upper and lower cut-off
frequencies in each band. Option 07 -
GAIN OPTION - other than 1-20. please specify maximal gain required. Option 09 -
DC OFFSET MEASUREMENT - on the test module with external BNC output. Option 10 -
HIGH CURRENT POWER SUPPLY - capable of driving up to 10 probes in 1:1 bridge
ratio as well as in x2 mode (up to 600mA per channel). Option 11 -
CCA (Constant Current Anemometer) in addition to CTA mode, with 31 fixed current
levels and a variable current of 0.3-30mA. Option 12 -
HIGH PERFORMANCE SIGNAL CONDITIONER - gain of 1-100 (1-200 optional) with 1-10
variable control and a gain multiplier of x1, x2, x5, x10. High accuracy DC
offset (2ppm/°C stability) with a variable control of 0-2V + fixed steps of
0,2,4,6,8 Volts. DC-off function. Use for low velocities and low turbulence
levels. Option 13 -
EXTERNAL POWER SUPPLY REMOVAL KIT - for removing the power supply to an external
rack for ultra high Noise Immunity. Option 14 -
AUTO-ZERO DC OFFSET - for automatic reduction of DC offset (use for Velocity
profiles or near wall). Control signals are TTL compatible (zero + read DC offset). Option 15 -
5m RG-58 COAXIAL PROBE CABLE.
Notes:
1. Probe protection and soft start circuits are standard on all channels.
2. All mainframes are built for 115/220Vac 50/60 Hz operation.
The
AN-1003 is a reliable Low- Cost, High performance, manual Hot-Wire Anemometry
system for measuring Fluid or Gas Velocity in up to 10 channels simultaneously.
The Hot-Wire Anemometer features 10 Analog channels, for Hot-Wire or Hot-Film
Sensors, with a built-in Signal Conditioner and Filter in each channel.
The operation of the system is simple and user friendly. Each channel has
a built in probe protection circuit, making it capable of operating very delicate
probes, with wires down to 0.6 micron. The anemometer also works with SenFlex® Hot-Film arrays made by Tao Systems Inc. (click on the link to Texas A&M Flight Research lab and select "Hot Wire and Hot Film Anemometry).
The operation of the system is completely manual, with no computer controls,
making it suitable for application where computer controlled and automated
systems would not work: Plasma measurements, Magneto Hydro Dynamics, Explosions,
Noisy Industrial applications etc. The AN-1003 system is tested for safety
according to European standartds and has a CE mark(for safety and Noise immunity).
All
noise parameters are correct for one or all channels working simultaneously.
Typical Output noise
5
µm Tungsten probe, OHR=1.5, U=0, B.W.=10 kHz
135
µ Vrms
The
same, with option 01
60
µ Vrms
Stability - Typical Input Drift
1:1
Bridge
0.5 µV/°C
1:10
Bridge
0.3 µV/°C
With
option 01 (all bridge ratios )
Less
than 0.1 µV/°C
Probe
cable
5 m of RG174 or RG58A
Output
Top of Bridge or amplifier output
CCA BRIDGE (Constant Current Anemometer, OPTION 11)
Fixed
currents
1,2,5,10,20 mA
Variable
current source
0.3-
30 mA
Selected current is displayed on test-Module
SIGNAL CONDITIONER
Output Voltages Range
±12V
Amplifier Gain (presetable to any gain in range)
1-20(can be ordered with 1-50 or 1-1000 ranges)
Gain accuracy
±0.5 %
DC Offset
0-10 V
Output Impedance
100 Ohm
Input Impedance
10
kOhm
Typical Input White Noise
30
nV
Frequency
Range
DC-100
kHz
Typical Equivalent Input Drift (Gain 1)
160 µV/°C
LOW-PASS FILTER
Triple-pole Butterworth Filter, with 12 Cut-off frequencies in 2 bands
Lower
band
300
Hz - 5 kHz (6 frequencies)
Upper
band
7
Hz - 16 kHz (6 frequencies)
Other
frequency bands can be ordered.
Mainframe
Specifications
POWER SUPPLY
Output Voltages
±15
V,±5 V
Maximum current (@ ±15 V)
4 A ( 7A with option 10 )
Hum and Noise
100
µ Vrms
Can drive 10 channels @ 1:10 bridge ratio,
or 5 channels @ 1:1 bridge ratio.
Option 10 can drive all ten channels in 1:1 or 1:10 modes,simultaneously.
TEST MODULE
Pulse Generator
Frequency
Voltage
2 kHz
Duty
Cycle
50% or 0.2%
Rise Time
50
nSec
Output
Voltages
0.1 V
Accuracy
100
ppm/°C, 0.1 %
Function
selects
Automatic
input/output connection according to selected function.
Channel Selector
Digitally controlled, gold plated contacts.
In normal operation, all channels except one are disconnected from the Test
Module, to prevent additional noise inputs from external devices
or cross-talking.
All
noise parameters are correct for one or all channels working simultaneously.
The Hot-Wire Anemometer works
with almost any Hot-Wire sensor and Hot-Film sensor made by any manufacturer.
Unit is CE rated (safety & noise & immunity).
The
typical frequency response sine wave test graph
was plotted according to data taken
from AN-1003 Hot-Wire Anemometer
with options 01 & 04. The amplitude
is normalized and relate to the 1 kHz amplitude.
.
