Experimental study on soot characteristics of laminar co-flow ethylene diffused flame under air atmosphere

School of Mechanical Engineering, Wanjiang University of Technology, Ma’anshan, 243031, China

^* Corresponding author: Jing Xu Email: xujing@hhuwtian.edu.cn

Abstract

The morphological characteristics of ethylene flame under different working conditions were photographed and analyzed by CCD camera, the temperature distribution at different positions of flame was measured and analyzed by the thermocouple, and the characteristics of soot in ethylene diffusing flame under different airflow rates were studied by means of SiC fiber sampling and subsequent TEM image analysis. The results showed that: (1) when the airflow was unchanged, the flame height increased with the increase of ethylene flow, and the flame height changed with the increase of ethylene flow in a linear relationship. When the ethylene flow increased from 120 mL/min to 180 mL/min, the flame height increased by about 60%. The flame height increased slightly with the increase in air flow. (2) The flame edge temperature was always greater than the central temperature of the corresponding height. Under the same working condition, the average temperature was 87.5 °C higher. (3) Along the flame axis, soot particles follow the process of nucleation, growth, condensation, agglomeration, and oxidation, and the four processes coexist. Once the flow rate of ethylene is determined, the generation of soot in each stage will lag when the flow rate of air increases.