“…Since Chien's paper was published in 1958 [1], boiler modeling has been commonly used for dynamics research [2,3], for control system design [4,5], and for optimal operation [6]. The evaporation system of a boiler receives heat from the flame inside the furnace, and its dynamic models based on physical principles for the evaporation system are very useful to analyze its transient characteristics which greatly influence the safe operation of the boiler.…”