You are here

LATTICE VIBRATION STUDY OF SILICA NANOPARTICLE IN SUSPENSION

Download pdf | Full Screen View

Date Issued:
2006
Abstract/Description:
In recent years considerable research has been done in the area of "nanofluids". Nanofluids are colloidal suspensions of nanometer size metallic or oxide particles in a base fluid such as water, ethylene glycol. Nanofluids show enhanced heat transfer characteristics compared to the base fluid. The thermal transport properties of nanofluids depend on various parameters e.g. interfacial resistance, Brownian motion of particles, liquid layering at the solid-liquid interface and clustering of nanoparticles. In this work atomic scale simulation has been used to study possible mechanisms affecting the heat transfer characteristics of nanofluids. Molecular dynamics simulation for a single silica nanoparticle surrounded by water molecules has been performed. Periodic boundary condition has been used in all three directions. The effect of nanoparticle size and temperature of system on the thermal conductivity of nanofluids has been studied. It was found that as the size of nanoparticle decreases thermal conductivity of nanofluid increases. This is partially due to the fact that as the diameter of nanoparticle decreases from micrometer to nanometer its surface area to volume ratio increases by a factor of 103. Since heat transfer between the fluid and the nanoparticle takes place at the surface this enhanced surface area gives higher thermal conductivity for smaller particles. Thermal conductivity enhancement is also due to the accumulation of water molecules near the particle surface and the lattice vibration of the nanoparticle. The phonon transfer through the second layer allows the nanofluid thermal conductivity to increase by 23%-27% compared to the base fluid water for 2% concentration of nanosilica.
Title: LATTICE VIBRATION STUDY OF SILICA NANOPARTICLE IN SUSPENSION.
16 views
7 downloads
Name(s): Sachdeva, Parveen, Author
Kumar, Ranganathan, Committee Chair
University of Central Florida, Degree Grantor
Type of Resource: text
Date Issued: 2006
Publisher: University of Central Florida
Language(s): English
Abstract/Description: In recent years considerable research has been done in the area of "nanofluids". Nanofluids are colloidal suspensions of nanometer size metallic or oxide particles in a base fluid such as water, ethylene glycol. Nanofluids show enhanced heat transfer characteristics compared to the base fluid. The thermal transport properties of nanofluids depend on various parameters e.g. interfacial resistance, Brownian motion of particles, liquid layering at the solid-liquid interface and clustering of nanoparticles. In this work atomic scale simulation has been used to study possible mechanisms affecting the heat transfer characteristics of nanofluids. Molecular dynamics simulation for a single silica nanoparticle surrounded by water molecules has been performed. Periodic boundary condition has been used in all three directions. The effect of nanoparticle size and temperature of system on the thermal conductivity of nanofluids has been studied. It was found that as the size of nanoparticle decreases thermal conductivity of nanofluid increases. This is partially due to the fact that as the diameter of nanoparticle decreases from micrometer to nanometer its surface area to volume ratio increases by a factor of 103. Since heat transfer between the fluid and the nanoparticle takes place at the surface this enhanced surface area gives higher thermal conductivity for smaller particles. Thermal conductivity enhancement is also due to the accumulation of water molecules near the particle surface and the lattice vibration of the nanoparticle. The phonon transfer through the second layer allows the nanofluid thermal conductivity to increase by 23%-27% compared to the base fluid water for 2% concentration of nanosilica.
Identifier: CFE0001278 (IID), ucf:46897 (fedora)
Note(s): 2006-08-01
M.S.M.E.
Engineering and Computer Science, Department of Mechanical, Materials, and Aerospace Engineering
Masters
This record was generated from author submitted information.
Subject(s): Nanoparticle
Nanofluid
Molecular Dynamics
Atomic Scale Simulation
Persistent Link to This Record: http://purl.flvc.org/ucf/fd/CFE0001278
Restrictions on Access: campus 2007-01-31
Host Institution: UCF

In Collections