The thermal and mechanical properties of concrete in which normal weight aggregate has been substituted with lightweight aggregates were investigated. The properties were found to be dependent on the volume fraction of the lightweight aggregate, as well as on the nature and quality of the aggregate. The addition of lightweight aggregates resulted in a decreased thermal conductivity, as well as a decreased thermal diffusivity in all samples. The compressive strength ...
The thermal properties (thermal conductivity, thermal diffusivity, and specific heat) were measured for igneous and sedimentary rocks at room temperature and atmospheric pressure. The thermal properties of the igneous rocks, dunite and gabbro, were then measured at temperatures ranging from 293 K to 483 K and 293 K to 443 K, respectively. A predictive model was then developed for estimating the effective thermal conductivity of porous media using the thermal conductivities of the solid ...
This article is based on research that has been done to improve hydrogen storage systems with on-board reversible metal hydrides. The study involved the compaction of the sodium aluminum hydride particles, as well as the addition of either aluminum or expanded natural graphite (ENG) to the powders to determine how their addition affects the thermal conductivity. It was found that the compaction of the powders improved the volumetric capacity of ...
High-strength steel used in bolts was tested for its thermo-physical properties in order to determine how steel bolts would respond in a fire. It was determined that the thermal and mechanical properties of the steel were dependent on temperature, and that the thermal conductivity of the steel was also dependent on carbon content. The thermal conductivity of the three types of steel that were tested was found to be the ...
Microcellular (methylmethacrylate)-(butyl acrylate)-(Methylmethacrylate) triblock copolymer foams were prepared by a foaming process using CO2. CO2 was first dissolved into sheets of the polymer, and then the pressure was released over different time periods, from 2 to 30 minutes. The density, cellular structure, and thermal conductivity of these foams were then investigated. It was determined that the density decreased with increasing depressurization time; however, the density did not change ...
