Coupled modeling of combustion and hydrodynamics for a 1000MW double-reheat tower-type boiler

Hydrodynamic calculation and safety evaluation are considered to be a key technology in the design of the water-cooled wall of double-reheat boilers. The accuracy of the assumed heat flux distribution directly affects the accuracy of these hydrodynamic calculations. In the present work, an in-house code was coupled with combustion simulation to study the hydrodynamic characteristics of the water-cooled wall of a 1000MW USC double-reheat boiler equipped with deep air-staging and flue gas recirculation. The heat flux distribution used in these calculations was obtained from the standard thermal deflection coefficient curve and from combustion simulation results. The calculation results of the outlet temperature of the water-cooled wall were then compared with in-situ experimental data. The results illustrate that the calculated temperature of the outlet of water-cooled wall based on the heat flux distribution obtained by combustion simulation agrees well with the actual operating conditions of the boiler. Conversely, large deviation was caused when the standard heat flux distribution curve was adopted. The present work demonstrates that combustion simulation coupled with hydrodynamics can be effectively used for design new types of boilers.