Design and Experiment of CO2 High Temperature Spectrum Parameter Measurement System

CO2 and CO2 are called the key indicators of combustion efficiency. Accurate measurement of CO2 in the combustion flow field is very important for energy conservation and emission reduction in industrial combustion process and engine combustion state diagnosis. Researching intensity, self-broadening full-width, temperature-dependence exponent and other parameters of CO2 in high temperature, may improve the accuracy and reliability of measurements for CO2 concentration. A precise temperature control and pressure control gas spectroscopic parameter measurement system with a design temperature up to 2073 K based on absorption spectroscopy has been developed for the measurement of spectroscopic parameters of the R (50e) line at 5 007.787cm(-1) of CO2. Many high temperature survey spectra of the CO2 R (50e) line were recorded at 1 212 similar to 1 873 K and many pressures through the system. Through background subtraction, baseline fitting, time-frequency conversion, multi-line combination and nonlinear least squares fitting, and other data processing based on the CO2 R (50e) survey spectra, intensity, self-broadening full-width and temperature-dependence exponent at 1 212-1 873 K were obtained. The uncertainty of line strength is less than 1.5%, the uncertainty of self-broadening full-width is less than 4. 5%. These parameters are supplement and improvement to the existing database. They are helpful for the detection of CO2 concentration in combustion diagnosis to ensure the accurate inversion of CO2 concentration in the combustion process.