To understand the inner wall temperature distribution characteristics of boiler heating surfaces during fast peaking operation

this study incorporates the coupling of non-uniform heat flux distribution on the combustion side with a multi-tube flow-resistance model on the working fluid side. This corrects the resistance and mass flow distribution among the rows of tubes in the superheater

forming a comprehensive heat transfer calculation model that couples the non-uniform heat flux on the flue gas side with the actual flow rate on the working fluid side

allowing for more accurate prediction of superheater temperatures. This model is applied to the calculation and analysis of wall temperature characteristics of a 660 MW counter-flow coal-fired boiler's screen superheater at various loads and swirl angles. The study reveals that during deep load-following

the highest tube wall temperature at 30% load(868.4 K) exceeds that at 50% load(861.9 K)

approaching the maximum temperature the material can withstand. The tube wall temperature at 50% load is higher than that at 75% load(849.7 K). Additionally

changes in swirl angle significantly affect the non-uniform distribution of flue gas and the working fluid temperature on the steam side. When the swirl angle is 45°

the high-temperature zone is primarily distributed at both ends of the tube screen. When the swirl angle is 15°

it concentrates in the middle front and middle rear regions. As the swirl angle increases

spatial heterogeneity of the flue gas field in the furnace enhances

leading to greater temperature non-uniformity across the superheater width. The research results can provide technical support for the design and retrofit of boilers during rapid load-following processes.