Entropy generation distribution characteristics of a supercritical boiler superheater during transient processes

Chaoyang Wang, Ming Liu, Yongliang Zhao, Daotong Chong and Junjie Yan

Energy, 2020, vol. 201, issue C

Abstract: A 1D dynamic modeling approach for surface heaters is developed and validated by comparing the calculation results with data from the available literature. Subsequently, the modeling approach is used for a superheater case study. The entropy generation of the superheater is calculated after undergoing step increasing the cold or hot inlet flow rate/temperature by 20%. The entropy generation for the hot side, the metal inside, the cold side, the entire heat transfer unit in different positions and the integral heater (ΔS˙TH) are presented and analyzed. Results show that increasing the cold/hot fluid flow rate enhances the heat transfer quantity (QT) and ΔS˙TH increase accordingly. With the increase in cold fluid inlet temperature, QT and ΔS˙TH decrease. For hot inlet temperature increasing, QT and ΔS˙TH increase. Additional entropy generation (ΔΔSTH) occurs due to the deviation between the real-time and the steady-state thermal status. The shares of ΔΔSTH are 0.7% and 6.7% during the transient process for the step increase in cold fluid inlet temperature and flow rate, respectively. ΔΔSTH accounts for 1.5% and 3.0% at the beginning of the step increase in the hot fluid inlet temperature and flow rate, respectively.

Keywords: Boiler superheater; 1D dynamic modeling; Transient processes; Entropy generation distribution; Irreversibility analysis (search for similar items in EconPapers)
Date: 2020
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (4)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544220307039
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:201:y:2020:i:c:s0360544220307039

DOI: 10.1016/j.energy.2020.117596

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().