On the problem of thermal link resistances in a.c. calorimetry

✍ Scribed by I.V. Velichkov

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 548 KB
• Volume: 32
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(92)90366-i

✦ Synopsis

The influence of the thermal link resistances between the parts of an a.c. calorimeter is analysed. A construction consisting of a substrate carrying the heater, the thermometer and the sample is considered. The calorimetric system is examined under the assumptions of constant and lumped parameters for the separate parts. Exact mathematical solutions are derived concerning the stationary amplitude Tac and the phase shift ~ of the thermometer readings with harmonic thermal disturbance on the system. The solutions are illustrated and analysed for some typical cases which are important from the practical point of view. The procedure to assess the quality of the thermal link between the sample and the substrate by means of the phase shift ¢ is shown and the possibility of obtaining accurate measurements under 'a.c. non-adiabatic' conditions at markedly lowered frequencies is considered.