|
| << previous | next >> |
Journal description
All volumes of the corresponding journal
All issues of the corresponding volume
All articles of the corresponding issues
Details for article 10 of 19 found articles
| Title: |
MULTIPOINT FIBEROPTIC HUMIDITY MONITOR |
| Author: |
Goldatein, N. Bien, F. Garah, M.E Lee, J. Zakin, M.R |
| Appeared in: |
Drying technology |
| Paging: | Volume 9 (1991) nr. 4 pages 833-847 |
| Year: |
1991 |
| Contents: |
Spectral Sciences, Inc. is developing a multipoint humidity monitor for drying application in the pulp and paper industry. The humidity is measured by monitoring near-infrared optical absorption in the process stream atmosphere. An array of sensor heads distributed throughout the plant is linked by fiber optic cables to a single source/readout device which can be located in a control room hundreds of meters away. The sensor heads and cables are modular. allowing for raid installation and reconfiguration of a distributed sensor system in process control applications. The method used for quantifying the optical absorption provides substantial stability, accuracy, and signal processing advantages over standard wavelength scanning or band pass techniques. The laser diode's output wavelength is actively locked to the center of a water absorption line, thereby providing a constant monitor of water vapor concentration which is insensitive to all other species in the process stream. Wavelength modulation and second harmonic detection techniques are used to quantify the water vapor concentration. A simultaneous temperature measurement then permits an output of the absolute humidity or humidity ratio for process monitoring or control |
| Publisher: |
Taylor & Francis |
| Source file: |
Elektronische Wetenschappelijke Tijdschriften |
Details for article 10 of 19 found articles
| << previous | next >> |