Combustion control using a multiplexed diode-laser sensor system

Douglas S. Baer; E. R. Furlong; Ronald K. Hanson

doi:10.1117/12.237729

Translator Disclaimer

8 April 1996 Combustion control using a multiplexed diode-laser sensor system

Douglas S. Baer, E. R. Furlong, Ronald K. Hanson

Author Affiliations +

Proceedings Volume 2703, Lasers as Tools for Manufacturing of Durable Goods and Microelectronics; (1996) https://doi.org/10.1117/12.237729
Event: Photonics West '96, 1996, San Jose, CA, United States

Abstract

A multiplexed diode-laser sensor system, comprised of two InGaAsP diode lasers and fiber- optic components, has been developed to non-intrusively measure temperature and species concentration over a single path for closed-loop process control using laser absorption spectroscopy techniques. The system was applied to measure and control the gas temperature in the post-flame gases 6 mm above the surface of a Hencken burner (multiple CH₄-air diffusion flames). The wavelengths of the lasers were independently current-tuned across H₂O transitions near 1343 nm (v₁ + v₃ band) and 1392 nm (2v₁, v₁ + v₃ bands), and temperature was determined from the ratio of measured peak absorbances. H₂O concentration was determined from the measured peak absorbance of one transition set at the measured temperature. The temperatures recorded using the sensor compared well with those measured by thermocouples. A computer-controlled closed-loop feedback circuit that actuated the fuel flow in response to the difference between the measured and desired gas temperature was used to control the flame temperature in the probed region. The results obtained with this first generation system demonstrate the potential of multiplexed diode lasers for rapid, continuous, in situ measurements and control of gasdynamic parameters in combustion environments.

Citation Download Citation

Douglas S. Baer, E. R. Furlong, and Ronald K. Hanson "Combustion control using a multiplexed diode-laser sensor system", Proc. SPIE 2703, Lasers as Tools for Manufacturing of Durable Goods and Microelectronics, (8 April 1996); https://doi.org/10.1117/12.237729

ACCESS THE FULL ARTICLE