Article

 

Large amplitude wavelength modulation spectroscopy for sensitive measurements of broad absorbers. Público Deposited

https://scholar.colorado.edu/concern/articles/r207tq09t
Abstract
  • We demonstrate large amplitude wavelength modulation spectroscopy (WMS) with a MEMS-tunable vertical cavity surface-emitting laser (MEMS-VCSEL) to measure high-density gases. WMS enables sensitive measurements of gas phase thermodynamic properties in harsh environments, but has been limited to moderate pressure and density conditions because of the narrow tuning range of traditional DFB lasers. The MEMS-tunable laser is able to rapidly modulate across the broadened features of high-density gas mixtures to produce the harmonic signals in the detected light intensity typical of WMS. We illustrate the technique on high-pressure mixtures of CO2 in air that are 2.5 times higher density than previously published WMS measurements (equivalent to greater than 255 atm at 1500 K). We develop a WMS model that accounts for nonlinear tuning of the laser to enable extraction of thermodynamic properties from measured data. The agreement of the measured data and model suggests that this technique could be used now for calibrated measurements of gas concentration, and in the future for calibration-free operation with further high-pressure absorption model development and laser tuning characterization.

Creator
Date Issued
  • 2016-11-28
Academic Affiliation
Journal Title
Journal Issue/Number
  • 24
Journal Volume
  • 24
File Extent
  • 27910-27921
Publisher
Última modificação
  • 2020-02-11
Identifier
  • PubMed ID: 27906360
Resource Type
Declaração de direitos
DOI
ISSN
  • 1094-4087
Language

Relações

Itens