Accurate prediction of tube surface temperature is important for deter
mining whether accelerated superheater corrosion will occur in kraft r
ecovery boilers. A heat transfer model, which combines an iterative nu
merical solution scheme with a more realistic flue-gas flow field obta
ined from a CFD code FLUENT, had been developed to predict the tube, s
team and flue-gas temperatures in the superheater region. Results of t
ests performed for a recovery boiler show that temperatures predicted
by the model are in good agreement with actual temperatures measured u
sing thermocouples. The presence of a large flue-gas recirculation zon
e above the bullnose is shown to have an adverse effect on the heat tr
ansfer in the superheater region.