EVERGREEN

Joint Journal of Novel Carbon Resource Sciences and Green Asia Strategy

ISSN:2189-0420 (Print until Mar 2020)
ISSN:2432-5953 (Online)

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Measuring Lubricant Concentration in the Mixture with Refrigerant: A Comprehensive Review

Isha Sameen1,*, Alaa Itaiwi1, Takahiko Miyazaki1,2, Yukihiro Higashi2, Kengo Hiratsuka3, Fujiwara Tomoya3, Kyaw Thu4,2
1Department of Advanced Environmental Science and Engineering Interdisciplinary Graduate School of Engineering Sciences, Kyushu University 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan
2Research Center for Next Generation Refrigerant Properties (NEXT-RP), International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Motooka, Nishi-ku, Fukuoka, Fukuoka 819-0395, Japan
3Advanced Technology R&D Center, Mitsubishi Electric Corporation, 8-1-1, Tsukaguchi-Honmachi, Amagasaki, Hyogo 661-8661, Japan
4Department of Advanced Environmental Science and Engineering Interdisciplinary Graduate School of Engineering Sciences, Kyushu University 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japa
*Author to whom correspondence should be addressed:
E-mail: isha.sameen.example@university.edu (IS)
Evergreen, Vol. 12, Iss. 02, pp. 1106–1130, 2025
DOI: 10.5109/7363498
Creative Commons Attribution 4.0 International Creative Commons Attribution 4.0 International
Received: December 09, 2024 | Revised: March 14, 2025 | Accepted: April 10, 2025 | Published: June 2025
Abstract
Lubricants in mechanical vapor compression systems play an important role in lubrication and thermal insulation. During system operation, small quantities of oil are observed to dissolve with working fluid. Oil migration from the compressor results in refrigerant lubricant mixture, which effects the thermophysical and thermodynamic properties of working fluid. A prediction of oil composition can help in determining properties in refrigerant/lubricant mixture. A lot of reviews have been published regarding to lubricants, their interaction with refrigerants, their thermophysical properties and effect on overall system. However, there is a need for systematic database for oil concentration evaluation methods. This review paper focuses on an overview of various techniques to measure oil concentration in refrigerant/lubricant mixtures. This review provides an overview of oil concentration evaluation methods based on various properties of the refrigerant lubricant mixture.
Keywords
Compressor ; Thermophysical properties ; Lubricant ; Refrigerant/lubricant mixture
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