Russian scientists have developed optical fiber sensors which can work under
high temperatures. Laboratory specimens can effectively operate under 1000 C
while the best foreign sensors lose their efficiency at temperatures as high as
300 - 400 C. A new-type fiber-optic waveguide has been developed on the basis of
unique chemical technologies dealing with plasma. To make optical fiber
structured
in these waveguides, nitrogen is used instead of germanium. Such sensors may be
used to solve numerous problems connected with measuring various physical
values, for example, temperature, mechanical stresses, pressure. The unique
sensor was created in Fiber Optics Research Center at the General Physics
Institute of Russian Academy of Sciences (RAS) owing to sponsor support of
Business-Unitech company.
Fiber-optic waveguides made from quartz glass alloyed with nitrogen have shown
a number of unique characteristics. Their ability to counteract
ionizing radiation exceeds that of standard fiber by an order of magnitude.
Therefore, innovated fibers can be widely used in aircraft
industry,in space-system engineering, at atomic stations and other units
which are of possible radiation danger. They can also be successfully used
in medicine jointly with laser, ultrasonic and ultra-high-frequency devices
where sensors of other kinds can hardly be helpful.
Also, the unique heat resistance of fibrous sensors
and their safety in explosions guarantees ceaseless monitoring while
measuring temperature and other parameters in petroleum and gas industry,
in turbines and engines, drying and heating installations as well as in
numerous furnaces. The sensors are absolutely insusceptible to electromagnetic
fields, therefore they can be used in technological processes where interference
is great because of electromagnetic noise. Under such conditions, it's almost
impossible to employ other means of control. One more advantage of the sensors
is that one can participate in monitoring paremeters of a potentially
dangerous object and remain at a safe distance from it (as far as a few
kilometers).
Similar tasks which are elaborated in foreign laboratories (for example, project
Optoplan AS) consume much more funds exceeding millions of dollars. Foreign
high-temperature tentative sensors, however, become invalid at temparatures as
high as 300 - 400 C, and the best industrial samples do not tolerate
temperatures more than 200 C.
Pioneering fiber-optic sensors targeted for commercial production are in
progress now owing to sponsor Business-Unitech. These will rest on the samples
available and are assumed to be high thermally stable. The sensors are
destined to measure temperatures, mechanical stresses, pressures, etc.
The first bargain has been concluded this year: SIMENS company has bought
a pilot lot for measuring temperatures in industrial turbines.
The most impressive though is an opportunity to create, on basis of innovated
fiber technology, various fiber-optic devices and a number of unique
fiber-optic elements which have no analogues in the world.
For the great achievements in the fiber optics, the team of developers were
awarded by a yearly Russian National Award.
http://www.cnews.ru
Translated by Natalya Lipunova