Optimized High-Temperature Irradiation-Resistant Thermocouple for Fast-Response Measurements

The high-temperature irradiation-resistant thermocouple is the only temperature probe proven to withstand (>1290°C), high-radiation (a fluence of up ?1 × 10 21 n/cm 2 ) environments nuclear reactor fuel design testing and/or over-temperature accident conditions. This report describes improved performance a molybdenum and niobium by utilizing coaxial (i.e., single wire grounded outer sheath). optimized features simplified yet allows for more robust individual components. thermoelements can be used interchangeably in either sheath or wire, depending on intended application. Via plunge test flowing water, response time build was determined 30x faster than that comparable ungrounded type-K thermocouples, 10x thermocouples traditional two-wire configurations). Furthermore, capitalizing design, multi-core with multiple “single-pole” wires along length feasible. multi-core, dubbed “demicouple.” demicouple primarily applied during experiments record fuel-pin centerline measurements using compact sensor. shared “common” leg between junctions reduces error propagation secondary such as differentials.