Thermoelectric (TE) generators have very important applications, such as emerging automotive waste heat recovery and cooling applications. This study investigates how thermal conductivity, seebeck coefficient, and resistivity of bismuth telluride changes with increasing isothermal aging. The thermal conductivity was tested with the Transient Plane Source (TPS) method. Both bismuth telluride n and p type were tested for 2 wk, 8 wk, 6 mo, 1 yr, and 2 yr of isothermal aging at 240 degrees Celsius. The ...
Aerogels have a wide range of properties that make them effective thermal insulators. However, these properties are lost when the materials absorb too much water. The goal of this experiment was to determine how temperature and humidity affect the insulative properties of silica nano-porous aerogels. A thermal constants analyzer measured the thermal conductivity of moist silica nano-porous materials using the transient plane source (TPS) method. Results showed that the thermal ...
Using the Transient Plane Source technique, various geopolymers, metakaolin-derived sodium (Na), sodium-potassium (NaK) and potassium (K), were tested to determine the effect of varying environmental conditions, such as temperature and humidity, on thermal conductivity. The results concluded that the thermal properties of the geopolymers derived from metakaolin are not greatly affected by the Si/Al ratio in the as-cured state. When the sodium geopolymers were tested at 50% relative humidity, the ...
