A porous matrix was prepared using low-density sawdust and a metakaolin-based geopolymer paste. The matrix was prepared in order to evaluate its performance as a thermally insulating building envelope. The matrices that had approximately 4 MPa of bi-axial four points flexural strength were prepared in a ratio of geopolymer paste:sawdust of between 1:1 and 1:1.5, and the thermal conductivity of these matrices was between 0.2-0.3 W/m·K....
Thermal conductivity, thermal diffusivity and specific heat are investigated for a granite rock sample from a deep borehole in central Portugal. Thirty-three samples were divided into two groups based on the degree of metasomatic alteration. It was found that the average thermal conductivity for the samples in the group comprising the less altered samples was 2.90 ± 0.26 W/m K, and for the more altered samples, the average value was 2.95 ± 0.19 W/m ...
The effective thermal conductivity of a commercial silica aerogel is determined at various gas pressures ranging from 0.001 Pa to 1 MPa in order to determine the contribution of gaseous heat conduction to the effective thermal conductivity of nano-porous materials. It was determined that the gas pressure had a significant effect on the effective thermal conductivity of the aerogel and that the contribution of gaseous heat conduction was greater than the gas ...
Nanoparticle suspensions were prepared in two PCMs to determine the effect of the addition of nanoparticles on thermal conductivity and expediting freezing. The base PCMs used were cyclohexane and eicosane, and copper oxide nanoparticles were suspended in these hydrocarbons to produce nano-enhanced PCMs (nePCMs). The enhancement of thermal conductivity and expedited freezing were investigated by analytic, experimental, and numerical methods. The thermal conductivity in the liquid phase was significantly enhanced ...
Styrene-butadiene (SBR) was added to high-density polyethylene (HDPE) to form a polymer blend. The thermal conductivity and thermal diffusivity of this polymer blend at room temperature were determined at varying blend compositions. The effects of dynamic crosslinking with sulfur crosslinking system and a mixed system on the thermal conductivity and diffusivity were also investigated. Finally, different models were evaluated for the estimation of thermal conductivity of a two phase system....
