A Combustion Diagnosis Method Based on Laser Absorption Spectroscopy with Wide Measurement Range

Abstract

The present invention relates to the technical field of combustion diagnosis, and relates to a laser absorption spectrum combustion diagnosis method with a wide measurement range, comprising the following steps: (1), determining the state parameter range of temperature T, component concentration X and pressure P, within the state parameter range Next, carry out the numerical simulation and optimization of absorption lines; (2), build the optical path of the experimental system based on the optimization results, and measure the absorption lines at the same time, which can be carried out by simultaneous measurement of multiple lines or time-division multiplexing technology Control the measurement of multiple spectral lines separately; (3), post-process the measured spectral signal, based on the spectral absorbance obtained after post-processing, use the optimization algorithm to calculate the temperature T, component concentration X and pressure P of the target gas The state parameters are inverted. The invention can expand the measuring range and improve the measuring accuracy.

Description

technical field [0001] The invention relates to the technical field of combustion diagnosis, in particular to a laser absorption spectrum combustion diagnosis method with a wide measurement range, in particular to a method for expanding the measurement range and improving measurement accuracy of laser absorption spectroscopy in combustion diagnosis. Background technique [0002] At present, combustion is still the main energy conversion method in the process of power production and power propulsion. Research and development of advanced combustion technology has always been one of the important goals of the scientific and industrial circles. For the measurement of the combustion process, with the advancement of science and technology, non-contact technologies such as laser measurement have developed rapidly. Compared with traditional contact measurements (such as thermocouples, etc.), laser combustion diagnosis technology has greater advantages and development potential in te...

AI Technical Summary

Problems solved by technology

However, for the two-line thermometry method widely used in absorption spectroscopy combustion diagnosis, there are still technical difficulties in the narrow measurement response range

In the case of using two absorption lines, although the temperature and concentration of the target molecule can be measured relatively simply and quickly, because the absorption intensity of the absorption lines changes significantly with temperature, it usually appears that the line selection for high temperature cannot be accurately determined. Measurement in the low temperature range area, or when the line selection for low temperature cannot accurately measure the state parameters in the high temperature area

This technical difficulty limits the application of absorption spectroscopy in scenes with a large temperature or concentration gradient of the target component, usually in the transition region where the temperature or concentration changes from a higher value to a lower value. The results cannot be measured directly in the area

At the same time, this technical difficulty also severely limits the possibility of using absorption spectroscopy to conduct more explorations in the field of basic combustion science

Even if methods such as tomography and multispectral imaging are combined, such as the combustion optimization control method based on multispectral absorption spectrum tomography technology proposed in the Chinese invention patent (CN107906555A), the effective sensing area of ​​absorption spectrum tomography is still limited.

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