Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Packing Hundreds of Sensors into a Single Optical Fiber for use in Harsh Environments

27.06.2014

New technology for gas flow measurement sets temperature record of 800 degrees Celsius -- ideal for use in deep drilling operations, nuclear reactor cores and outer space

By fusing together the concepts of active fiber sensors and high-temperature fiber sensors, a team of researchers at the University of Pittsburgh has created an all-optical high-temperature sensor for gas flow measurements that operates at record-setting temperatures above 800 degrees Celsius.


An artist's rendering of the fiber optic flow sensor. The glowing red sections along the optical fiber are the sensors--hundreds of these sensors can be packed into a single fiber. Image credit: Kevin Chen, University of Pittsburgh.

This technology is expected to find industrial sensing applications in harsh environments ranging from deep geothermal drill cores to the interiors of nuclear reactors to the cold vacuum of space missions, and it may eventually be extended to many others.

The team describes their all-optical approach in a paper published today in The Optical Society’s (OSA) journal Optics Letters. They successfully demonstrated simultaneous flow/temperature sensors at 850 C, which is a 200 C improvement on an earlier notable demonstration of MEMS-based sensors by researchers at Oak Ridge National Laboratory.

The basic concept of the new approach involves integrating optical heating elements, optical sensors, an energy delivery cable and a signal cable within a single optical fiber. Optical power delivered by the fiber is used to supply energy to the heating element, while the optical sensor within the same fiber measures the heat transfer from the heating element and transmits it back.

“We call it a 'smart optical fiber sensor powered by in-fiber light',” said Kevin P. Chen, an associate professor and the Paul E. Lego Faculty Fellow in the University of Pittsburg’s Department of Electrical and Computer Engineering.

The team’s work expands the use of fiber-optic sensors well beyond traditional applications of temperature and strain measurements. “Tapping into the energy carried by the optical fiber enables fiber sensors capable of performing much more sophisticated and multifunctional types of measurements that previously were only achievable using electronic sensors,” Chen said.

In microgravity situations, for example, it’s difficult to measure the level of liquid hydrogen fuel in tanks because it doesn’t settle at the bottom of the tank. It’s a challenge that requires the use of many electronic sensors—a problem Chen initially noticed years ago while visiting NASA, which was the original inspiration to develop a more streamlined and efficient approach.

“For this type of microgravity situation, each sensor requires wires, a.k.a. ‘leads,’ to deliver a sensing signal, along with a shared ground wire,” explained Chen. “So it means that many leads—often more than 40—are necessary to get measurements from the numerous sensors. I couldn’t help thinking there must be a better way to do it.”

It turned out, there is. The team looked to optical-fiber sensors, which are one of the best sensor technologies for use in harsh environments thanks to their extraordinary multiplexing capabilities and immunity to electromagnetic interference. And they were able to pack many of these sensors into a single fiber to reduce or eliminate the wiring problems associated with having numerous leads involved.

“Another big challenge we addressed was how to achieve active measurements in fiber,” Chen said. “If you study optical fiber, it’s a cable for signal transmission but one that can also be used for energy delivery—the same optical fiber can deliver both signal and optical power for active measurements. It drastically improves the sensitivity, functionality, and agility of fiber sensors without compromising the intrinsic advantages of fiber-optic sensors. That’s the essence of our work.”

Based on the same technology, highly sensitive chemical sensors can also be developed for cryogenic environments. “The optical energy in-fiber can be tapped to locally heated in-fiber chemical sensors to enhance its sensitivity,” Chen said. “In-fiber optical power can also be converted into ultrasonic energy, microwave or other interesting applications because tens or hundreds of smart sensors can be multiplexed within a single fiber. It just requires placing one fiber in the gas flow stream—even in locations with strong magnetic interference.”

Next, the team plans to explore common engineering devices that are often taken for granted and search for ways to enhance them. “For fiber sensors, we typically view the fiber as a signal-carrying cable. But if you look at it from a fiber sensor perspective, does it really need to be round or a specific size? Is it possible that another size or shape might better suit particular applications? As a superior optical cable, is it also possible to carry other types of energy along the fibers for long-distance and remote sensing?” Chen noted. “These are questions we’ll address.”
 
Paper: “Fiber-optic flow sensors for high-temperature-environment operation up to 800°C,” R. Chen at al., Optics Letters, Vol. 39, Issue 13, pp. 3966-3969 (2014).
 
EDITOR’S NOTE: An artist’s rendering of the sensor is available to members of the media upon request. Contact Angela Stark, astark@osa.org.
 
About Optics Letters
Published by The Optical Society (OSA), Optics Letters offers rapid dissemination of new results in all areas of optics with short, original, peer-reviewed communications. Optics Letters covers the latest research in optical science, including optical measurements, optical components and devices, atmospheric optics, biomedical optics, Fourier optics, integrated optics, optical processing, optoelectronics, lasers, nonlinear optics, optical storage and holography, optical coherence, polarization, quantum electronics, ultrafast optical phenomena, photonic crystals, and fiber optics. This journal, edited by Xi-Cheng Zhang of the University of Rochester and published twice each month, is where readers look for the latest discoveries in optics. Visit www.OpticsInfoBase.org/OL.
 
About OSA
Founded in 1916, The Optical Society (OSA) is the leading professional society for scientists, engineers, students and business leaders who fuel discoveries, shape real-world applications and accelerate achievements in the science of light. Through world-renowned publications, meetings and membership programs, OSA provides quality research, inspired interactions and dedicated resources for its extensive global network of professionals in optics and photonics. For more information, visit www.osa.org.

Angela Stark | Eurek Alert!
Further information:
http://www.osa.org/en-us/about_osa/newsroom/news_releases/2014/packing_hundreds_of_sensors_into_a_single_optical/

Further reports about: OSA Packing Sensors environments fiber heating measurements optics sensing temperature

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>