Research on identification of vortex structure in oxy-fuel heating furnace based on vortex identification method

ABSTRACT

MILD oxy-fuel combustion has become the subject of study as it can improve the combustion efficiency and reducing the emission of harmful gases. However, there are few researches on the vortex motion of Oxy-fuel combustion, and there is no clear definition for the application of gas vortex. In this paper, based on the experimental and simulation data of the heating furnace, the distribution of eddy motion was analyzed from aspects of the turbulent vortex formation, formation, and movement of the vortex. In this paper, the vortex structure of the furnace is analyzed by using the Q criterion, ${\lambda }_2$ method, and $\mathrm{\Omega }$ method. We found that both Q criterion, ${\lambda }_2$ criterion, and $\mathrm{\Omega }$ method could identify the vortex structure in the furnace, but $\mathrm{\Omega }$ method could identify the vortex structure that could not be identified by the other two methods. $\mathrm{\Omega }$ could display more vortex structures and could identify both weak and strong vertices, with stronger recognition ability.

KEYWORDS:

• Oxy-fuel
• q criterion
• ω criterion
• vortex structure
• heating furnace

Additional information

Funding

This study was financially supported by the National Natural Science Foundation of China (Grant No. 51964039, 51464041, 51164025) and the National Natural Science Foundation of Inner Mongolia (Grant No. 2018MS05009).