Publication detail

Dynamic study of the extraction ratio and interstage pressure ratio distribution in typical layouts of SCO2 Brayton cycle under temperature fluctuations

Zhang, L., Klemeš, J.J., Zeng, M., Wang, Q.

Original Title

Dynamic study of the extraction ratio and interstage pressure ratio distribution in typical layouts of SCO2 Brayton cycle under temperature fluctuations

Type

journal article in Web of Science

Language

English

Original Abstract

Supercritical CO2 Brayton cycle is widely used in industry because of its small compression work and considerable cycle efficiency. In this work, dynamic simulation numerical models of Supercritical CO2 Brayton cycle with three typical layouts (recompression, reheating, intercooling) and a newly proposed layout are developed using thermodynamic equations. After verifying the simulated steady-state values with the experimental ones, key parameters in the recompression and the new layout, as well as their responses under temperature perturbations, are calculated for different extraction ratios. It has been found that larger extraction ratios correspond to lower efficiency but higher stability, and similarly, the new proposed layout is 4.1% less efficient but with a 34% smaller fluctuation amplitude compared to the recompression layout. Then system parameters are calculated for different interstage pressure ratio assignments for the turbine in the reheating model and for the compressor in the intercooling model. The results show the 1st-stage with a pressure ratio of 1.2 has higher power generation and cycle efficiency, as well as more stable generated power. For the newly proposed layout, the pre-compressor power, as well as the fluctuation amplitude of the (RC + IC + PC) model, is much larger than the other compression powers, and the fluctuation amplitude from largest to smallest are IC, (RC + IC + PC), RC, RH. The effects of extraction ratio on efficiency and generated power are much greater than the distribution of interstage pressure ratio, and the maximum efficiency is obtained at the small extraction ratio and the equal pressure ratio of the two stages.

Keywords

Brayton cycle; Extraction ratio; Pressure ratio distribution; Supercritical CO2; Transient response; Wave amplitude

Authors

Zhang, L., Klemeš, J.J., Zeng, M., Wang, Q.

Released

25. 7. 2022

Publisher

Elsevier Ltd

ISBN

1359-4311

Periodical

Applied Thermal Engineering

Number

212

State

United Kingdom of Great Britain and Northern Ireland

Pages from

118553

Pages to

118553

Pages count

14

URL

https://www-sciencedirect-com.ezproxy.lib.vutbr.cz/science/article/pii/S135943112200504X

BibTex

@article{BUT178078,
  author="Jiří {Klemeš}",
  title="Dynamic study of the extraction ratio and interstage pressure ratio distribution in typical layouts of SCO2 Brayton cycle under temperature fluctuations",
  journal="Applied Thermal Engineering",
  year="2022",
  number="212",
  pages="118553--118553",
  doi="10.1016/j.applthermaleng.2022.118553",
  issn="1359-4311",
  url="https://www-sciencedirect-com.ezproxy.lib.vutbr.cz/science/article/pii/S135943112200504X"
}