Analytical prediction of Reynolds-number effects on miniaturized centrifugal compressors under off-design conditions

Andrés Sebastián, Rubén Abbas and Manuel Valdés

Energy, 2021, vol. 227, issue C

Abstract: The use of micro-scale centrifugal compressors in closed-loop thermodynamic cycles working with fluids different than air is gaining in importance in novel miniaturized energy systems. Miniaturization implies a decrease in the Reynolds number, which usually entails efficiency drops. The aim of this paper is to study the low-Reynolds-number effects on the performance of micro-scale centrifugal compressors under off-design conditions. Consequently, an analytical prediction method is formulated to characterize the efficiency variations using different working fluids and pressurization factors. A numerical model of a reference micro-scale compressor is developed to assess the degree of agreement between the results obtained by these two methods. The results show the Reynolds-number effects on the whole characteristic map of the reference compressor for air, carbon dioxide, propane and isobutane. These fluids were chosen according to their efficiency increase potential, which is measured by a proposed Reynolds-number-based estimator. Although some divergences have been identified, the agreement between analytical and numerical results can be considered to be globally satisfactory. Efficiency increases in the range of 2–6% points are obtained with slight pressurization factors using air or carbon dioxide. These variations could even achieve a rise of 9 pp in the case of propane and isobutane.

Keywords: Micro-scale centrifugal compressors; Low Reynolds-number; Off-design performance; Turbomachinery miniaturization (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S036054422100726X
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:227:y:2021:i:c:s036054422100726x

DOI: 10.1016/j.energy.2021.120477

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 ().