Readdressing working fluid selection with a view to designing a variable geometry ejector

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Szabolcs Varga (Author) FEUP; Pedro Lebre (Author) FEUP; Armando C. Oliveira (Author) FEUP

Journal

Title: International Journal of Low Carbon Technologies

Vol. 10

Pages: 205-215

ISSN: 1748-1317

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 15 Citations

ISI Web of Science

Scopus - 26 Citations

Scientific classification

FOS: Engineering and technology

CORDIS: Technological sciences

Other information

Authenticus ID: P-00H-Q5Q

DOI: 10.1093/ijlct/ctt026

Abstract (EN): A number of factors influence the performance of an ejector, e.g. working fluid, geometry and operating conditions. In the present work, six low-environmental-impact working fluids were evaluated for their use in an ejector cooling system running on low-temperature thermal energy. The numerical analysis was based on a model applying the 1D constant-pressure mixing theory. Ejector performance was assessed for the temperatures of the generator, evaporator and condenser in the range of 80-120 degrees C, 5-15 degrees C and 25-40 degrees C, respectively. The results indicated that owing to its high coefficient of performance and moderate operating pressures throughout the entire ejector cycle, isobutane is a good choice for a refrigerant. The area ratio required for running the ejector in critical mode, under changing operating conditions, varied in a significant range regardless of the selected refrigerant. This clearly indicates the importance of a variable geometry ejector design to strengthen the position of ejector cooling systems among other refrigeration technologies.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11