Numerical study on the enhanced heat transfer characteristics of steam generator with axial economizer

The heat transfer enhancement of heat exchangers is vital to improve energy utilization efficiency in industrial fields. The axial economizer used in steam generator is a typical enhanced heat transfer device. In this paper, the mechanism of heat transfer enhancement in steam generator with axial economizer was studied and the key thermal hydraulic parameters in steam generator were analyzed. The effects of divider plate heights and flow distribution on the heat transfer characteristics were also investigated. Results show that the axial economizer can effectively increase the heat exchange up by 2% and the steam production up by 3%. Within a certain range (0–2.2 m), the increase of divider plate height is beneficial for heat transfer enhancement. The flow distribution on the hot and cold sides would affect the heat transfer obviously. The influence of flow distribution on the heat transfer in steam generator is mainly concentrated in the cold side region. The conclusions can provide references for the design and operation of a new steam generator with the axial economizer, and are also meaningful for the enhancing heat transfer research in other industrial fields involving shell-and-tube heat exchangers.