Temperature monitoring options available at the Idaho national laboratory advanced test reactor

Abstract

Abstract. As part of the Advanced Test Reactor National Scientific User Facility (ATR-NSUF) program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. Clearly, temperature sensor selection for irradiation tests will be determined based on the irradiation environment and budget. However, temperature sensors now offered by INL include a wide array of melt wires in small capsules, silicon carbide monitors, commercially available thermocouples, and specialized high temperature irradiation resistant thermocouples containing doped molybdenum and niobium alloy thermoelements. In addition, efforts have been initiated to develop and evaluate ultrasonic thermometers for irradiation testing. This array of temperature monitoring options now available to ATR and other Material and Test Reactor (MTR) users fulfills recent customer requests.

Chalcogenide Glass-Capped Fiber-Optic Sensor for Real-Time Temperature Monitoring in Extreme Environments

“…So far, this has been a big challenge due to radiation–material interaction at high temperatures. Usually, in any high-radiation environment (e.g., reactor cladding, and spent fuel pool), the temperature is monitored using metal-based sensors like thermocouples, Resistance Temperature Detectors (RTD), or melt-wire sensors [ 4 , 5 ]. Although RTDs give real-time data about temperature, RTDs need external current to measure the resistance change.…”

“…Additionally, the sensor performance is affected by oxidation and the temperature readings drift significantly under long-duration exposure to high temperature and radiation [ 6 , 7 ]. This often necessitates sensor recalibration due to transmutation from absorption of neutrons [ 4 ].…”

Additive Manufacturing of Miniaturized Peak Temperature Monitors for In-Pile Applications

“…Melt wires are a passive monitoring technique that enables identification of the peak temperature achieved during an irradiation test [14]. This method involves placing wires of a known composition and well-characterized melting temperature within an experimental test capsule designed for materials testing.…”

“…The library of qualified materials for melt-wire selection contains more than 40 useful materials with a detection range between 29.73 • C and 1535 • C [15]. Wire materials are chosen based on expected irradiation test temperatures and required temperature measurement resolution [14]. While classical melt wires are commonly used in test-reactor experiments, such as those conducted in the ATR, some test designs have limited space due to predesigned capsules that may only be a couple of millimeters in diameter.…”

Recovery of Silicon Carbide monitor irradiation temperature via continuous resistance measurement during annealing (Pt. II)

“…Silicon carbide (SiC) monitors are routinely used for measurement of peak irradiation temperature in nuclear irradiation experiments in research reactors like the Nuclear Science User Facilities -Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) Daw et al, 2013). Irradiation of the monitors at a specific temperature results in lattice structural changes that can be removed by annealing (Littler, 1962;Huang and Ghoniem, 1997).…”