Boiler heat transfer is significantly different to that of a typical industrial process and needs to be analyzed and modelled using purpose-built software. This software must incorporate features to address the following issues and nuances of steam raising plant:

• Radiation tends to play a dominant role in the overall heat transfer and requires a significantly more complex assessment than other heat transfer modes.
• Heating surfaces can have unusual configurations and orientations with respect to gas flows making heat transfer performance difficult to assess.
• Extended fin (including square gill) tubing used to recover low grade heat at the back end of many boilers requires algorithms which are not normally available in industrial heat exchanger and process analysis software.
• Superheater temperature control needs very specific attention in any modelling exercise. Spray attemperation can have a profound effect on superheater metal temperatures and the steam and spraywater configuration paths can be complicated by the use of so called “sweet water condensers”. Alternatively, non-contact attemperation systems also need special consideration as they are normally incorporated into the boiler’s internal circulation system .
• Accurate assessment of water cooled enclosures and cavity heat absorption can have a significant impact on the accuracy of boiler performance predictions and internal circulation modelling results.
• Boilers often utilize airheating systems which can be difficult to analyse accurately.