As buildings are constructed, pores and cavities are formed within the building envelope and can cause issues with coupled transient radiation-natural convection heat transfer. This research aims to develop a model to minimize the empty space in the area lining the exterior and interior of the building (building envelope). As cavities and pores are present within the building envelope, issues of heat loss and high energy consumptions arise. An improved ...
A new application for the transient hot-wire technique for thermal conductivity measurements has been described. It is intended to provide an accurate means of implementation of the method to the determination of the thermal conductivity of solids exemplified by a standard reference ceramic material. Measurements of the transient temperature allows an absolute determination of the thermal conductivity of the solid. The uncertainty achieved for the thermal conductivity is better than ±1%, ...
Thermal conductivity and thermal diffusivity of two poly(methyl methacrylates) were measured using multiple methods; temperature wave analysis, laser flash, transient plane source, transient line-source probe, and heat flux meter. The main reasoning behind this study was to compare results between methods, to ensure repeatability among methods. Good agreement was shown among thermal conductivity and thermal diffusivity results between instruments, however the transient plane source method repeatedly yielded 6% higher results ...
To evaluate the effect of climate change on the stability of methane hydrates in the seafloor, thermal conductivity measurements were performed in hydrate-bearing sediment. Using the renormalization and labeling technique methods, alongside of a thermal constants analyzer, the effective thermal conductivity (ETC) of methane hydrate-bearing sand and tetrahydrofuran (THF) hydrate-bearing sand were measured and found to be 1 W/mK and 2 W/mK, respectively. The thermal ...
When thermal conductivity and diffusivity are measured with a thermal constants analyzer, sensors of different designs are being used. Sensors are primarily made of nickel foil, arranged in a double spiral, sandwiched between two thin sheets of insulating material. For experiments between 30 and 450 K, the polyimide Kapton has been used as the insulating material. For experiments being performed at temperatures above 450 K, but below 1000 K, Mica can be used as ...
