Calculation Code for Helically Coiled Heat Recovery Boilers

This paper describes a calculation code developed for helically coiled heat recovery boilers fed with exhaust gases from internal combustion engines, gas turbines or industrial processes. The code carries out the thermal rating calculation of the boiler by means of a one-dimensional model applicable to either water or thermal oil heating or steam generation in a once-through configuration. The paper is focused on the first case, in which cold fluid phase-change does not occur, and illustrates how the rating program can be helpful to improve the boiler design with respect to the current standard, allowing a reduction of several percentage points in the calculated heat transfer area (and correspondingly weight and material cost) required for a given duty.