The thermal properties of five sandstones were measured. The sandstones were taken from the base of Khewra located in Pakistan. The thermal conductivity, thermal diffusivity, and specific heat capacity were determined using the transient plane source technique, and the porosity and density of the sandstone samples were also determined. A formula for the estimation of thermal conductivity was modified to better fit the experimental data, and it was determined that ...
Thermal energy storage (TES) is incredibly important to expanding the field of renewable energy. In this study, the authors look at the potential of composite phase change materials (PCMs) for use in this application. A ball milling method was used to exfoliate expanded graphite in nanosheets that could be added to eicosane to create composite materials. Composites with nanosheets of various sizes were created, and the effect of cooling rate ...
This paper proposes conducting carbon aerogels, composed of graphene and multi-walled carbon nanotubes, as an option for a thermoelectric material. The researchers found that this combination of materials increased the electrical conductivity and the Seebeck coefficient due to bridging effects, and decreased the thermal conductivity through high porosity and a uniquely structured 3-D skeleton. Atomic force microscopy and X-ray diffraction were used to quantify the physical structure of the aerogels. ...
In an effort to be more environmentally friendly, the construction industry is investing more in 'green' concretes and insulation materials. The purpose of this research was to create a porous foam using a geopolymer mixture and varying amounts of silica carbide sludge. By changing the amount of the sludge added, researchers could control what type of microstructure was produced. The effect of this variation on porosity and thermal properties was ...
As electronics get smaller and more powerful, the packaging that contains them must in turn become lighter with higher thermal conductivity and electrical resistivity. This study tested the effect of adding highly concentrated hexagonal boron nitride (hBN) fibers to liquid crystal polymer. The fibers were oriented in a way to achieve a high filler concentration, and the composites were then randomly added to a polyactide matrix. The researchers found that ...