{"title":"Linear variations in conductivity and viscosity as particles’ basic profile for convective instability in nanofluids under various boundary conditions","authors":"Jyoti Sharma","doi":"10.1007/s11012-024-01784-4","DOIUrl":null,"url":null,"abstract":"<div><p>The present study investigates thermal sensitivity of a horizontal nanofluid layer which is subjected to conductivity and viscosity variations as linear functions of volume fraction of particles. A weak heterogeneous characteristic of the fluid is considered i.e. variations freeze as the basic profile of particles in the system. Further, the study undertakes various boundary conditions on the layer to analyse the convection process such as zero particle flux, equal, top and bottom heavy distribution of volume fraction of particles. The expression of Rayleigh number for nanofluid is found to be increased significantly due to conductivity and viscosity variation effects and has negligible impact in decreasing/increasing its value due to other nanofluid variables. Thus, a substantial enhancement in the stability of the system is established except for zero flux case where overall effects due to the presence of particles become almost negligible. The properties of base fluid and particles show conflicting roles in deciding the thermal sensitivity of the layer.</p></div>","PeriodicalId":695,"journal":{"name":"Meccanica","volume":null,"pages":null},"PeriodicalIF":1.9000,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Meccanica","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11012-024-01784-4","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
The present study investigates thermal sensitivity of a horizontal nanofluid layer which is subjected to conductivity and viscosity variations as linear functions of volume fraction of particles. A weak heterogeneous characteristic of the fluid is considered i.e. variations freeze as the basic profile of particles in the system. Further, the study undertakes various boundary conditions on the layer to analyse the convection process such as zero particle flux, equal, top and bottom heavy distribution of volume fraction of particles. The expression of Rayleigh number for nanofluid is found to be increased significantly due to conductivity and viscosity variation effects and has negligible impact in decreasing/increasing its value due to other nanofluid variables. Thus, a substantial enhancement in the stability of the system is established except for zero flux case where overall effects due to the presence of particles become almost negligible. The properties of base fluid and particles show conflicting roles in deciding the thermal sensitivity of the layer.
期刊介绍:
Meccanica focuses on the methodological framework shared by mechanical scientists when addressing theoretical or applied problems. Original papers address various aspects of mechanical and mathematical modeling, of solution, as well as of analysis of system behavior. The journal explores fundamental and applications issues in established areas of mechanics research as well as in emerging fields; contemporary research on general mechanics, solid and structural mechanics, fluid mechanics, and mechanics of machines; interdisciplinary fields between mechanics and other mathematical and engineering sciences; interaction of mechanics with dynamical systems, advanced materials, control and computation; electromechanics; biomechanics.
Articles include full length papers; topical overviews; brief notes; discussions and comments on published papers; book reviews; and an international calendar of conferences.
Meccanica, the official journal of the Italian Association of Theoretical and Applied Mechanics, was established in 1966.