Category: Transient Plane Source
Author(s): Dan Clary
Abstract: Colloid chemistry has been of interest for many years. Researchers have begun to study the effects of metal particles on the stability and thermal properties of cooling liquids. The purpose of this study was to introduce metal particles to a solvent, resulting in a stable and thermally enhanced colloid. To serve as a reducing agent and a particle stabilizer, a cyclodextrin-glucose host-guest complex was synthesized to create aqueous metal colloids. Multiple sample versions were tested: crystalline copper (II) oxide particles, Ag, Au, Pd and Pt and copper. The resulting colloid from the crystalline copper (II) oxide particle suspension had modest stability and resistance to air, however was susceptible to drying and being redispersed in a variety of low dielectric media. The resulting colloids from the Ag and Pt suspensions displayed an increase in thermal properties and were stable for four plus months. It was determined that as the number of metal particles nears zero, enhanced thermal properties are noted. The metallic copper colloid had high stability, enhanced thermal properties, but was sensitive to air. Based on the tests performed, it is safe to say that further measurements, other than just thermal conductivity are required to accurately characterize nanofluids.
Reference: Doctorate Thesis - Auburn University (2011)