2023/02/10 by Jamie Luke McMillan, McMillan, Jamie Luke
Engineering · #Calibration and Measurement Techniques #FOS: Physical sciences #Infrared Target Detection Methodologies #Instrumentation and Detectors (physics.ins-det) #Thermography and Photoacoustic Techniques
paper · pdf · doi:10.48550/arxiv.2302.05198
openalex publication_date 2023/02/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Despite being regarded as a well-established field, temperature measurement continues to pose significant challenges for many professionals in the metrology industry. Thermal imagers enable fast, non-contact and a full field measurement, however there is a lack of metrological development to support their use. Here, thermal imagers have been examined for the monitoring of special nuclear material containers; the surface temperature is an important parameter for store management decisions. Throughout this research: a selection of thermal imagers were calibrated and made traceable to the International Temperature Scale of 1990; laboratory observations of a proxy steel plate were made; initial measurement of nuclear material storage containers were made; then a deployment to an inactive store was demonstrated. For this technique to be feasible, uncertainties less than 10^∘C would be required. During the laboratory calibration of an uncooled and cooled thermal imager against blackbody reference sources, across the measured temperature range of 10^∘C to 100^∘C the uncertainties were less than 3.20^∘C (k=2) and 0.50^∘C (k=2) respectively. Here k is the uncertainty coverage factor. When these calibrations were applied to the plate, regions of steel and higher emissivity coating were evaluated. These uncoated regions were measured with a thermal imager to demonstrate temperature differences compared to surface mounted thermocouples of 8.3^∘C and uncertainties up to 30.1^∘C (k=2). For the coated regions this temperature difference was reduced to 1.8^∘C with uncertainties up to 6.8^∘C (k=2).