The Influences of Temperature, Concentration and Pressure Uncertainties on the Measurement Results of Wavelength Modulation Spectroscopy

Gas temperature, species concentration, and pressure uncertainties inevitably affect the measurement results of wavelength modulation spectroscopy. We analyze and calculate the influences of these uncertainties on CO₂ concentration and temperature measurement results. Calculation results show that uncertainties in the pressure and CO₂ concentration have little influence on temperature measurement results. On the contrary, CO₂ concentration measurement results are notably influenced by pressure uncertainty, and greatly influenced by temperature uncertainty. To solve these problems in the temperature, species concentration, and pressure uncertainties, we take the experimental data from the previous study and analyze them using the iteration method with the purpose of obtaining the optimal values of gas temperature and CO₂ concentration.