Numerical Simulation of a 330 MW Tangentially Fired Boiler by a Model Coupling CFD and Hydrodynamic Calculation

The interaction mechanism of multi-physical fields in a 330 MW tangentially fired boiler is explored by coupling the CFD (computational fluid dynamics) model and the working fluid side hydrodynamic model under steady-state conditions. The research focuses on the flue gas flow field, the hydrodynamic safety of the water wall, the variation of the working fluid parameters and the formation and distribution characteristics of sulfide (SO 2 , H 2 S) under different steady loads (35%, 50%, 75%, 100% Boiler Maximum Continuous Rating). The results show that under high load, the flue gas attaches to the wall. The overall stagnation differential pressure ratio (1.85–2.07) and reversal differential pressure ratio (1.22–1.30) of the G1 tube group with the lowest heat flux are higher than the safety threshold (1.05), proving reliable operational safety under equilibrium conditions. The temperature distribution of the furnace center obtained by numerical simulation is consistent with the actual situation. The mass fraction of sulfide increases significantly with the increase in load. SO 2 is mainly distributed in the wall area of the middle and upper burners, while H 2 S is mainly distributed in the wall area between the secondary air and the main burner. The maximum mass fractions of SO 2 and H 2 S at 330 MW are 0.120% and 0.0524%, respectively. It is suggested that a wall-attached air system be added to inhibit the enrichment of corrosive gases. This work may provide theoretical support and engineering guidance for multi-objective optimization design and high temperature corrosion prevention and control of tangentially fired boilers.