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Be sure to check out our ad on the back
cover of the current issue of Aerospace
America
AUR Product Highlights
- Miniature Position Resolving Three-velocity component
LDV: A first in the world
- AUR Studio LDV Burst Processor
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Laser-Doppler Velocimetry: 2010 updates for a
classic
technique
June 2010
© Applied University Research, Inc.
AUR LDV's make obtaining useful flow velocities time and
cost efficient.
Many have experienced the
exacerbation of firing up an aging
laser-Doppler velocimeter/anemometer (LDV), and all of its attendant
support hardware, only to find that major work was in order to make the
system operational. Maybe the bulky, inefficient ion laser was far out
of alignment or the signal processing unit could not be interfaced with
your facility host computer. Worse yet, perhaps the laser tube was long
out of commission or the uni-tasking processing unit would not even
boot up. We frequently hear about similar issues with aging LDV
equipment.
By implementing 2010 technology and unmatched experience, such problems
are a thing of the past with AUR's high performance LDV systems. Here
are some examples of past issues and AUR's solutions that make our
systems workhorses of today's advanced flow facilities:
Issue: Instrument set-up is time consuming and
difficult.
Solutions: Stable-pointing diode-pumped solid state
(DPSS) lasers, precision thermal control, superior mechanical design
and intuitive, robust control software yield a system that requires a
minimum of instrument setup. In most cases, simply mount the probe and
begin measurements.
Issue: LDV measurements are time consuming for the
amount of information gained.
Solutions: AUR's LDV systems offer automated
operation, the highest valid data rates and advanced
data post-processing options that reduce measurement time and effort
and enhance the
interpretation of the information available in the data.
Issue: LDV particle seeding is messy, cumbersome,
fickle and a source of uncertainty.
Solutions: AUR will analyze your facility to
provide the best seeding materials and generation methods to meet your
needs. We offer the VAPCON, a carefully controlled
vaporization/condensation seeder, for extremely narrow particle size
distributions (±12% of the mean diameter
bounds most of the particles), taking the guessing out of particle
response in complex flows. We also have extensive experience seeding
and measuring separating flows with intense shear layers and will offer
this experience in specifying the solutions for your applications. We
can also specify seeding for high temperature flows!
Issue: LDV fails where access through curved walls
is required.
Solutions: AUR is the world leader in making
velocity measurements through curved facility walls, making use
of two
technologies. First, AUR personnel have used thin shell windows in
low-to-moderate dynamic pressure flows for many years with great
success. Our
ultra-miniaturized SM3LDV probe may be located inside of models
under test and peer up two 1.18" out from the model to measure the
crucial details of complex flows over three-dimensional surfaces.
Further, our 'Comprehensive'
LDV technologies allow customers to measure entire profiles of
velocities without traversing the probe! For cylindrical windows,
entire planes of data may be obtained by traversing parallel to the
cylinder axis. No other manufacturer offers these capabilities.
Issue: Complicated and bulky multiple-color systems.
Solutions: AUR's newest generation of LDV systems
offers three-velocity-component measurements using a single nominal
laser wavelength (532nm)! State-of-the-art photonics design and
integration leads to a simple single photodetector configuration. The
benefit of this simplicity is greater efficiency in photodetection,
fewer optical and fiber optic components, and the ability to use
robust, high powered, advanced DPSS lasers operating at 532nm.
Issue: Quirky,
uni-tasking
signal
processing
and
data
acquisition hardware.
Solutions: AUR Studio, our ultra-configurable
measurement and automation software, is LDV measurement-ready with the
most advanced burst processing suite in use today. With the LabView
option, the system may be integrated into your complex experimental
control VI's with ease. The PC-based unit gives you control over the
measurement process and is re-configurable for other measurements or
instruments as needed. Templates for 'modules', the processing
workhorses of AUR Studio, are supplied with all units for end-user
custom processing and post-processing applications.
About AUR:
Applied University Research, Inc. develops advanced technologies for
flow velocimetry and control. Founded by Dr. Roger L. Simpson, a
prominent researcher in turbulent flow mechanics and instrumentation
for over 35 years and past president of AIAA, AUR leverages unique
capabilities and knowledge to deliver solutions to flow problems.
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Applied University Research, Inc.
Ph: 540.797.0643
FAX: 866.223.8673
605 Preston Ave.
Blacksburg, VA 24060
http://www.aurinc.com
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Research
Facilities:
6580 Valley
Center Drive
Suite 317, Bay 160
Radford, VA 24141
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