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Near-Infrared Temperature Measurement Technique for Water Surrounding an Induction-heated Small Magnetic Sphere
Published on: April 30, 2018
Absorption measurements of water-vapor concentration, temperature, and line-shape parameters using a tunable InGaAsP
Applied Optics
|September 22, 2010
Summary
A new laser absorption technique accurately measures water vapor concentration and temperature. This method provides crucial data for H(2)O line strengths and self-broadening coefficients, validated in various environments.
Area of Science:
- Spectroscopy
- Laser diagnostics
- Atmospheric chemistry
Background:
- Accurate measurement of water vapor is crucial for various scientific and industrial applications.
- Traditional methods for water vapor detection can be complex or lack precision.
- Developing advanced laser-based diagnostics offers a promising alternative.
Purpose of the Study:
- To develop and validate a tunable diode laser absorption spectroscopy (TDLAS) system for precise water vapor detection.
- To determine water vapor concentration, temperature, and collision-broadening parameters.
- To measure H(2)O line strengths and self-broadening coefficients.
Main Methods:
- Utilized a distributed feedback InGaAsP diode laser emitting at ~1.38 µm.
- Employed current modulation for wavelength tuning (1 cm(-1) at 80 Hz).
- Analyzed spectrally resolved absorption spectra in static cells and flame environments.
Main Results:
- Successfully measured water vapor concentration and temperature in laboratory air and methane-air flame gases.
- Accurately determined H(2)O line strengths and self-broadening coefficients.
- Results showed excellent agreement with calculated values and independent measurements.
Conclusions:
- The developed TDLAS system is a reliable tool for in-situ water vapor measurement.
- The study provides valuable spectroscopic data for H(2)O.
- This technique has potential applications in combustion analysis, environmental monitoring, and process control.
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