New Photonics Lab Works on Sensors for Harsh Environments
Jun Wang (G) tests a sensor developed
at Virginia Tech that will withstand the harsh environment in
an oil well. The sensor is expected to last multiple years in
full operation, as opposed to current sensors, which last only
about 300 hours.
The Department has established a new laboratory to develop
photonic sensors for harsh environments.
The new Photonics Laboratory, directed by Anbo
Wang, currently has more than $3 million in funding, a six
faculty and staff members, and 10 Ph.D. and M.S. students-with
plans to add five research members this spring. The research
program is supported by three laboratories.
"We do research in three major areas: fiber optic sensors
for harsh environments, miniaturized 3-D imaging, and fiber components
for communications and sensors," Wang said. "The sensor
devices and instrumentation systems we develop are primarily
for those applications where conventional sensors are difficult
to apply due to the harsh environments involved. Typical harsh
environments include high temperature, high pressure, high voltage,
strong EMI and chemically corrosive atmospheres.
At present, the group's largest project involves developing oil
well sensors with ultrahigh resolution and accuracy that can
be used in harsh environments. The project is supported by a
three-and-a-half-year, $2-million contract from the U.S. Department
of Energy (DOE).
The project builds on the team's recent development of a self-calibrated
interferometric/intensity-based (SCIIB) sensor, which for the
first time successfully combined fiber interferometry and intensity-modulated
devices together in a single sensor system. The sensor can withstand
temperatures up to 800° C and pressures up to 20,000 p.s.i.
Sensors developed with SCIIB technology are expected to last
several years in service, according to Wang. Current commercial
down-hole sensors last only about 300 hours after installation,
"With reliable sensors, oil companies can get accurate information
about conditions in the wells and reservoirs, which could yield
more efficient and economical oil recovery," he said.
Another harsh-environment project involves developing sensors
for gas turbine engines, where high-temperature/high-pressure
sensors are short-lived. "We expect our sensors to withstand
higher temperatures, exhibit better reliability, and provide
higher accuracy and higher frequency response," Wang said.
Sponsored by Rolls Royce, Photonics Laboratory researchers are
collaborating with Wing Ng, a professor of mechanical engineering.
Other sensors that the Photonics Laboratory is developing will
be part of a complex system to detect earthquake-induced fires
and signal the extent and location to the necessary response
teams. The project is sponsored by Maryland-based InfraTech and
involves researchers from a wide range of disciplines.
Equally critical are sapphire fiber sensors that the team is
developing for the power industry. The project is sponsored by
the National Science Foundation (NSF) and the Electric Power
Research Institute (EPRI). "Sapphire is a promising material
for the fabrication of optical fiber sensors," Wang explained.
"It has a high melting temperature (above 2000º C),
has excellent optical transmission properties, has a high hardness
and elastic modulus, and is impervious to most chemicals,"
he added. The sensors fabricated with sapphire optical waveguides
are expected to be capable of operation at temperatures above
Other Laboratory projects include developing special optical
fibers for sensing and communications, fiber acoustic sensors
for the detection and location of partial discharges in power
transformers, fiber optic 3-D imaging for robot navigation, and
optical fiber-based rotary communication devices for the medical
Faculty members involved in the Photonics Laboratory are Wang,
Ahmad Safaai-Jazi, and Russell May.