Measurement on Gas Number Density Distribution by Tunable Diode Laser Absorption Spectroscopy

Abstract:

An experimental technique was designed to measure the gas number density distribution of alkali vapor by tunable diode laser absorption spectroscopy. The measurement method was developed by scanning multiple gas absorption lines and fitting the experiment data with Lorentz profile to obtain the density. A discretization strategy of the equation for absorption lines is also present here as well as a constrained liner least-square fitting method. A simulation model was set up to reconstruct the two-dimensional distribution of number density and the feasibility of the reconstruction was verified. In the end, this work demonstrates the calculation error of the acquired number density and the distribution. The results indicated that the error would be no more than 5% if the measurement error is less than 9%.

• Periodical: Advanced Materials Research (Volumes 986-987)
• Pages: 1523-1526
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.986-987.1523
• Online since: July 2014
• Authors: Hui Jie Zheng, Wei Quan*
• Keywords: Atomic Absorption Spectrometry, Discretization Method, Gas Number Density Distribution

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