Experimental investigation of an organic Rankine cycle with liquid-flooded expansion and R1233zd(E) as working fluid
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
A new concept of liquid-flooded expansion has been proposed as a performance increasing modification of the basic ORC targeted at low-temperature heat sources. However, little research demonstrates the potential of this technology especially experimentally. In this paper, an experimental test facility based on a conventional recuperative ORC system was constructed with an independent liquid flooding loop that enables testing the influence of liquid flooding on a modified single-screw expander as well as on the cycle itself. Experiments were performed at various pressure ratios (3.3–4.1) over the expander and flooding ratios (0–0.3) with R1233zd(E) as the working fluid and a standard lubricant oil as the flooding medium. The data reduction and uncertainty analysis were also discussed in depth. In total, 142 steady-state points were obtained. Compared with the baseline organic Rankine cycle, the maximum improvement of the liquid-flooded expansion on the expander power output can be 9.1%, although at slightly worse expander inlet conditions. The maximum enhancement of the isothermal efficiency of the expander was 9.5%. Results also showed that the expander power output, the net power output and the thermal efficiency were enhanced with the increase of the flooding liquid amount. The potential of an organic Rankine cycle system with liquid-flooded expansion can be further examined if over-expansion losses can be reduced and larger amount of oil can be injected, i.e., with higher pressure ratios and higher flooding ratios. Overall, this study provides insights into performance improvement by means of modifying the cycle thermodynamics itself.
Date Issued
2021-04
Date Acceptance
2021-01-24
Citation
Energy Conversion and Management, 2021, 234, pp.1-20
ISSN
0196-8904
Publisher
Elsevier BV
Start Page
1
End Page
20
Journal / Book Title
Energy Conversion and Management
Volume
234
Copyright Statement
© 2021 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://www.sciencedirect.com/science/article/pii/S0196890421000716?via%3Dihub
Grant Number
EP/P004709/1
EP/R045518/1
Subjects
Energy
0906 Electrical and Electronic Engineering
0913 Mechanical Engineering
Publication Status
Published
Article Number
113894
Date Publish Online
2021-03-06