{"title":"Mechanism of enhanced boiling heat transfer by hydrophilic and hydrophobic hybrid deposited nanoparticles: A molecular dynamics simulation","authors":"Zhao Wang , Zhenfu Tian","doi":"10.1016/j.ijheatmasstransfer.2024.125893","DOIUrl":null,"url":null,"abstract":"<div><p>The present work utilizes Molecular Dynamics (MD) method to study the physical mechanism of the effect of hybrid deposited nanoparticles (HDNs) on the boiling heat transfer by changing the wettability of the substrate. Three kinds of nanofluid simulation models are established, in which water molecules are used as the base fluid, and nanoparticles are hydrophilic deposited particles, hydrophobic deposited particles and HDNs, respectively. Compared with hydrophilic and hydrophobic deposited nanoparticles, it is found that the equilibrium contact angles of droplet containing HDNs decreases by 2.22° and 6.99° respectively during wetting simulation, indicating that HDNs improve the wettability of the substrate. By simulating the boiling process of three fluids, it is found that HDNs advance the start time of explosive boiling by 0.15 ns at most, that is, accelerate the nucleation time of bubbles, and increase the heat flux by 46.9 % at most, indicating that the heat convection near the substrate is enhanced. In addition, HDNs improve the vibration matching degree of atoms between the solid-liquid interface and enhance the heat transfer between the substrate and the fluid. The results of boiling simulation verify the conclusion that HDNs improve the wettability of the substrate and thus enhance the heat transfer inferred by droplet wetting simulation.</p></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":null,"pages":null},"PeriodicalIF":5.0000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Heat and Mass Transfer","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0017931024007245","RegionNum":2,"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
The present work utilizes Molecular Dynamics (MD) method to study the physical mechanism of the effect of hybrid deposited nanoparticles (HDNs) on the boiling heat transfer by changing the wettability of the substrate. Three kinds of nanofluid simulation models are established, in which water molecules are used as the base fluid, and nanoparticles are hydrophilic deposited particles, hydrophobic deposited particles and HDNs, respectively. Compared with hydrophilic and hydrophobic deposited nanoparticles, it is found that the equilibrium contact angles of droplet containing HDNs decreases by 2.22° and 6.99° respectively during wetting simulation, indicating that HDNs improve the wettability of the substrate. By simulating the boiling process of three fluids, it is found that HDNs advance the start time of explosive boiling by 0.15 ns at most, that is, accelerate the nucleation time of bubbles, and increase the heat flux by 46.9 % at most, indicating that the heat convection near the substrate is enhanced. In addition, HDNs improve the vibration matching degree of atoms between the solid-liquid interface and enhance the heat transfer between the substrate and the fluid. The results of boiling simulation verify the conclusion that HDNs improve the wettability of the substrate and thus enhance the heat transfer inferred by droplet wetting simulation.
期刊介绍:
International Journal of Heat and Mass Transfer is the vehicle for the exchange of basic ideas in heat and mass transfer between research workers and engineers throughout the world. It focuses on both analytical and experimental research, with an emphasis on contributions which increase the basic understanding of transfer processes and their application to engineering problems.
Topics include:
-New methods of measuring and/or correlating transport-property data
-Energy engineering
-Environmental applications of heat and/or mass transfer