Thermorheological properties of nanostructured dispersions

Nanostructured dispersions, which consist of nanometer-sized particles, tubes, sheets, or droplets that are dispersed in liquids, have exhibited substantially higher thermal conductivities over those of the liquids alone. While it is desirable to synthesize a fluid that has improved heat transfer characteristics, it is necessary that the viscosity remain low, so as not to appreciably increase the pumping power needed to employ these fluids in "real world" applications. To this end, the theological and thermal properties of twenty-six different nanostructured dispersions were examined. In terms of rheometry, both steady flow and creep tests were employed, while the transient hot wire technique was utilized to perform measurements of the thermal conductivity of each fluid. Characterization of the dispersed phase was completed using dynamic light scattering and transmission electron microscopy. In particular, the dispersion properties examined were nanostructure material, nanoparticle size, base fluid material, nanostructure concentration, and presence of a surfactant. It was observed that several of the fluids or nanopowders obtained from commercial manufacturers either contained no particles, had the presence of a relatively large proportion of water in ethylene glycol-based fluids, or were composed of particles with sizes far in excess of those claimed by the manufacturer.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Gordon, Jeremy B

Advisor dc:contributor.advisor

• Gareth H. McKinley.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39866

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39866