ISSN Online: 2377-424X
ISBN Print: 0-89116-909-1
International Heat Transfer Conference 9
EFFECTS OF FINITE PROBE DIAMETER AND PROBE HEAT CAPACITY ON MEASUREMENTS BY THE THERMAL CONDUCTIVITY PROBE
Resumo
The conjugated one dimensional transient conduction problem during heat transfer from a cylindrical heat source to an infinite medium surrounding the heat source is analysed analytically and numerically. The temporal variation of the heat source temperature predicted in this study is directly related to the measurement of thermal conductivity using the transient wire heat source technique or a thermal conductivity probe. It is found that measurements based on the classical theory of the transient wire heat source technique may lead to errors in experimental estimation of thermal conductivity if the heater thermal capacity is different from the thermal capacity of the material under test or if the test is conducted within a period just after the start of a measurement. Results from the present analysis yields a measure for errors in experimental estimation of thermal conductivity. The magnitude of error introduced can be approximately determined from the dimensionless graph presented in this study.