The present paper addresses the measurement errors in temperature due to the effects of surface-mounted temperature sensors like thermocouples. Heat conduction into or from the installed thermocouple wires can alter the temperature at the thermocouple junction as well as in its immediate vicinity. As a result, the emf appearing at the thermocouple terminals does not correspond to the actual surface temperature. In this paper, we present a dual-scale computational method that can be used to calculate the transient temperatures at the multiple thermocouple junctions during heating or cooling of an object. The basis of the method is a thermocouple submodel embedded in a FEM model for the parent object. The numerical results of the dual-scale computational model are compared with that of the conventional FEM models as well as the analytical solutions available. This paper also discusses the characteristics of surface-mounted thermocouples in a range of configurations.

Issue Section:
Research Paper
Keywords:
Heat Transfer, Measurement Techniques, Numerical Methods, Thermocouples, temperature measurement, physics computing, measurement errors, temperature sensors, thermocouples, heat conduction, finite element analysis
Topics:
Computational methods, Errors, Junctions, Temperature, Thermocouples, Wire, Temperature measurement, Finite element methods, Finite element model
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