{"title":"An improved equivalent viscosity model for the bubbly oil under high shear rate","authors":"Shaohua Li, Shuyun Jiang, Xiaohui Lin, Chibin Zhang","doi":"10.26599/frict.2025.9441042","DOIUrl":null,"url":null,"abstract":" <p>Shear-thinning effect of pure oil and distribution of bubble size are essential factors affecting the viscosity of bubbly oil. This study aims to establish an improved equivalent viscosity model for bubbly oil by considering the shear-thinning effect and the bubble distribution effect. Based on the equivalence principle of frictional resistance, the viscosity of pure oil considering the shear thinning effect is derived; based on the energy conservation principle, the viscosity increment due to bubble deformation is derived. A series of experiments, including generation of bubbly oil, bubble observation, and measurement of bubble oil viscosity, are conducted to validate the model established. The simulated and experimental results indicate that the improved equivalent viscosity model of bubbly oil is more accurate than the traditional model. Notably, the effect of oil shear thinning on the equivalent viscosity is much more obvious than the effect on the distribution of bubble size.</p> ","PeriodicalId":12442,"journal":{"name":"Friction","volume":"19 1","pages":""},"PeriodicalIF":6.3000,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Friction","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.26599/frict.2025.9441042","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Shear-thinning effect of pure oil and distribution of bubble size are essential factors affecting the viscosity of bubbly oil. This study aims to establish an improved equivalent viscosity model for bubbly oil by considering the shear-thinning effect and the bubble distribution effect. Based on the equivalence principle of frictional resistance, the viscosity of pure oil considering the shear thinning effect is derived; based on the energy conservation principle, the viscosity increment due to bubble deformation is derived. A series of experiments, including generation of bubbly oil, bubble observation, and measurement of bubble oil viscosity, are conducted to validate the model established. The simulated and experimental results indicate that the improved equivalent viscosity model of bubbly oil is more accurate than the traditional model. Notably, the effect of oil shear thinning on the equivalent viscosity is much more obvious than the effect on the distribution of bubble size.
期刊介绍:
Friction is a peer-reviewed international journal for the publication of theoretical and experimental research works related to the friction, lubrication and wear. Original, high quality research papers and review articles on all aspects of tribology are welcome, including, but are not limited to, a variety of topics, such as:
Friction: Origin of friction, Friction theories, New phenomena of friction, Nano-friction, Ultra-low friction, Molecular friction, Ultra-high friction, Friction at high speed, Friction at high temperature or low temperature, Friction at solid/liquid interfaces, Bio-friction, Adhesion, etc.
Lubrication: Superlubricity, Green lubricants, Nano-lubrication, Boundary lubrication, Thin film lubrication, Elastohydrodynamic lubrication, Mixed lubrication, New lubricants, New additives, Gas lubrication, Solid lubrication, etc.
Wear: Wear materials, Wear mechanism, Wear models, Wear in severe conditions, Wear measurement, Wear monitoring, etc.
Surface Engineering: Surface texturing, Molecular films, Surface coatings, Surface modification, Bionic surfaces, etc.
Basic Sciences: Tribology system, Principles of tribology, Thermodynamics of tribo-systems, Micro-fluidics, Thermal stability of tribo-systems, etc.
Friction is an open access journal. It is published quarterly by Tsinghua University Press and Springer, and sponsored by the State Key Laboratory of Tribology (TsinghuaUniversity) and the Tribology Institute of Chinese Mechanical Engineering Society.