A transient method with pulse heating has been developed to determine the specific heat and thermal conductivity of Bakelite (phenol-formaldehyde resin) in the temperature range of 4.44-9.15K. The temperature excursion in an infinite cylinder with an insulated outer surface and with a cylindrical heat source embedded in it was calculated initially. In the calculation, the heat source released heat as a rectangular-shaped pulse in the time direction. The ratio of the temperature rise at any two time instances was found to be a function only of the Fourier numbers associated to those instances. Therefore, by measuring that ratio, thermal diffusivity was determined while the specific heat could be calculated by the ultimate temperature rise. It was recognized in the temperature range tested that the specific heat and thermal conductivity increased with temperature while the thermal diffusivity decreased with it. The temperature dependence of the specific heat measured is similar to that for Formite Bakelite varnish in the literature.
|Number of pages||4|
|Journal||Transactions of the Japan Society of Mechanical Engineers Series B|
|Publication status||Published - 1988|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanical Engineering