Abstract:

 To address the problems of flow deviation and vortices easily caused by flue gas mixing in the transition section of large double radiant section ethylene cracking furnaces, CFD numerical simulation technology was adopted to systematically study the effects of transition section width, groove structure and side wall inclination angle on the flow field taking this type of cracking furnace in a certain plant as the research object. The results show that the transition section width is a key parameter affecting flow field uniformity, and different width schemes have a significant impact on achieving flow field uniformity. The side wall inclination angle has little effect on the flow field, while the groove structure can improve the flow field but is difficult to implement in engineering due to its complex structure. Finally, a structure of "transition section bottom width benchmark + 350 mm + benchmark side wall inclination angle" is recommended, which provides technical support for the operation of double-hearth cracking furnaces.

Key words: double radiant section, ethylene cracking furnace, transition section, numerical simulation