Operation of a thermal comparator
- 1 December 1979
- journal article
- Published by IOP Publishing in Journal of Physics E: Scientific Instruments
- Vol. 12 (12) , 1129-1132
- https://doi.org/10.1088/0022-3735/12/12/002
Abstract
Describes the improvement of a simple thermal comparator for distinguishing between diamond and its common substitutes, by the incorporation of a resistive heater. Essentially, the heater raises the temperature of one junction of a copper-constantan thermocouple while the other junction is cooled by the material under test. This note describes measurements of the time response of the comparator and of the dependence of the output EMF upon the thermal conductivity of the test sample, together with some observations on the effect of specimen thickness. It is shown that the behaviour of the comparator fits a model that consists of a network of five thermal resistors.Keywords
This publication has 2 references indexed in Scilit:
- A simple thermal comparator for testing gemstonesJournal of Physics E: Scientific Instruments, 1979
- Measurement of thermal conduction by the thermal comparatorJournal of Scientific Instruments, 1962