Optical analysis of and chemiluminescence in sooting flames

MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology - Nanjing 210094, PRC and Advanced Combustion Laboratory, School of Energy and Power Engineering, Nanjing University of Science and Technology - Nanjing 210094, PRC

Received: 3 October 2025
Accepted: 15 December 2025

Abstract

As flame spectra contain important flame information, this study presents a novel hyperspectral information processing method for CH^* and chemiluminescence visualization in hydrocarbon diffusion flames under various operating conditions. Flames spectral information of 400–1000 nm is obtained using a hyperspectral camera. Onion peeling algorithm is used to reconstruct the flame radiation. The calculated exact intensity of the soot radiation is subtracted from the total radiation to obtain CH^* and chemiluminescence intensity. Experimental results show that the proposed approach can effectively eliminate strong interference from soot radiation, obtaining CH^* and chemiluminescence information under different combustion conditions, indicating the robustness and adaptability of the method. This work provides valuable insights for the development of advanced flame sensing techniques and real-time combustion diagnostic systems.