Numerical Investigation on Metrological Fidelity of a Shielded Thermocouple Probe and the Effects of Geometrical Parameters

Proper design optimization and precise error characterization of temperature sensing-elements are rudimentary in the field of high accuracy gas temperature measurements. The intricate flow structures and heat transfer mechanisms related to a shielded thermocouple probe are studied in this paper using computational fluid dynamics and conjugate heat transfer (CFD/CHT) simulation tools. Owing to the probe's novel geometry, it was a pre-requisite to characterize the metrological fidelity of the probe and the steady-state errors were determined from the simulations. The influence of certain geometrical parameters on the error characteristics of the probe was also investigated. The characteristic variation of the metrological fidelity of the probe with respect to those geometrical parameters should facilitate the optimization of the probe design.