Industrial boiler damage is a common phenomenon encountered in boiler operation normally which usually lasts several decades. Since boiler shutdown may be required because of localized failures, it is crucial to predict the most vulnerable parts. If damage occurs, it is necessary to perform root cause analysis and devise corrective measures (repairs, design modification, etc.). Boiler tube bundles, such as those in superheaters, preheaters and reheaters, are the most exposed and often the most damaged boiler parts. Both short-term and long-term overheating are common causes of tube failures. In these cases, the design temperatures are exceeded, which often results in decrease in remaining creep life. Advanced models for damage evaluation require temperature history, which is available only in rare cases when it has been measured for the whole service life. However, in most cases it is necessary to estimate the temperature history from available operation history data (inlet and outlet pressures and temperatures etc.). The task may be very challenging because of the combination of complex flow behavior in the flue gas domain and heat transfer phenomena. This paper focuses on estimating thermal load on superheater tubes via Computational Fluid Dynamics (CFD) simulation of flue gas flow including heat transfer within the domain consisting of a furnace and a part of the first stage of the boiler.

This work is supported by: Research project No. TA13401000 “Waste-to-Energy (WtE) Competence Centre”