Sensors
Source: Pacific Northwest Laboratory
Date: 8/1/95    Record No.: 10187
Contact: John Hartman, 509-375-2771

Sensors
There is no specifically organized function to manage sensor development at PNL. Instead, there are a large number of informally linked "islands" of expertise across the lab's organization. John Hartman offers to help pull together the appropriate people to address any particular need or application.

It's also important to note that sensors are only one of a long list of technical areas that comprise PNL's "Automation and Measurement Sciences Department," including robotics, imaging, NDE, instrumentation, and applied mechanics.

PNL views sensors in the context of the entire process and environment they operate in. Starting with a long list of basic sensing mechanisms, a cost-effective and practical device must be developed, together with the associated components to form a sensor system. The sensor system in turn must fit functionally into the larger system of which it is a part.

Thus, the development of a sensor system must draw on a wide range of talents.

Mechanisms include electrochemical, electromagnetic, chemical interaction, mechanical, optical, radiological interaction, electromechanical, and thermoelectric. Practical sensors measure the presence, amount or concentration of chemical species or radiation, mechanical strain, moisture, crack growth, acoustics, fluid flow properties, temperature, em fields, or corrosion. Implementation must take into account materials, signal characteristics, response rates, fabrication, stability, on-board signal handling, packaging, power requirements, calibration, etc. Finally, the balance of system must deal with how the sensor data is transferred and used, in terms of the process hardware, software and human interaction.

Some examples:

Fiber-optic Chemical sensors monitor ground water contamination, using emission, absorption or color-change phenomena.
Piezoelectric Chemical sensors detect small quantities of a chemical species with selective coatings.
Acoustic and Ultra acoustic sensors are applied in diverse areas such as sonar, materials inspection, and near-surface geophysical exploration. Measuring the time of flight of a sound pulse, PNL developed a system to measure the internal temperature of steel at temperatures up to 2000 F. It is now in use in a steel plant's continuous caster.
Optical sensors have applications ranging from power-beaming in space, to high speed production inspection, to remote temperature measurement.

[For further inquiry: H2 detection is very important for Hanford, and a group at PNL probably has done work in this area that might prove useful for nuclear power plants.]

Topics:
Keywords: