Multi-parameter reconstruction of combustion field in confined space based on nonlinear absorption bispectral deflection tomography

Combustion diagnosis is often based on optical methods based on laser and radiation, such as laser absorption spectroscopy, Raman, etc., to measure temperature and component concentration by detecting changes in spectral signals. Tomographic absorption spectroscopy has attracted much attention due to its ability to achieve in-situ multi-parameter measurement, and there is a challenge of light deflection in confined spaces and under high pressure and high temperature conditions. The traditional linear method is difficult to deal with the nonlinear deflection problem. Therefore, this paper proposes a nonlinear absorption dual-spectral deflection tomography technology, which improves the measurement accuracy.