Through the addition of copper oxide nanoparticles to cyclohexane in varying concentrations, a series of nano-enhanced phase change materials (NePCM) were prepared. The transient plane source (TPS) technique was used to characterize the NePCM at multiple temperatures. It was determined experimentally that increasing concentrations of nanoparticles in the liquid phase resulted in increasing thermal conductivity, but increasing nanoparticle concentration in the solid phase didn't have the same effect.Unidirectional freezing ...
Surfactants are often used in nanofluids to help improve dispersion and prevent aggregation of the resident nanoparticles. In this study, the researchers used the transient plane source (TPS) technique to measure the thermal conductivity of a variety of nanofluids with different surfactants of varying concentrations, at different temperatures and pH values. For surfactants, thermal conductivity stabilizes after the addition of a certain concentration of that surfactant. Strongly acidic and alkaline ...
Thermal interface resistance results from small gaps and surface geometry mismatches between two materials that make up a composite. Thermal interface resistance is present in most any material that is comprised of two or more components. In the field of thermal interface materials, the majority of novel materials are composites, and thus are subject to thermal interface resistance and thermal boundary resistance (thermal discontinuity at a perfectly bonded interface of ...
Using Al2O3 nanoparticles, de-ionized water, and different volume fractions of two surfactants, Al2O3/water nanofluids were prepared by a two-step method. Thermal conductivities of the nanofluids were measured by the thermal constants analyzer. The choice of surfactant used (either sodium dodecyl sulfate (SDS) or polyvinylpyrrolidone (PVP)) had an influence on the thermal and mechanical properties of the nanofluids. PVP was found to be better at stabilizing the nanofluid, ...
High speed microscopy was used to allow real time visualization of the movement of nanoparticles made up of single-walled carbon nanotubes (SWCNT) and Fe2O3. An electrostatic force was induced to the nanotube/Fe2O3 composite and caused perfect conjugate structures which result in excellent thermal, electrical, and mechanical properties. The alignment of the carbon nanotubes in nanosuspensions may offer new opportunities for the development of nanofluids....
