Low-Drift Ultra-High Temperature Thermal Sensors

No drift-free measurement of temperature exists for monitoring in-core reactor temperatures in planned Gen-IV nuclear reactor designs, especially the next generation nuclear plants such as the VHTR (very high temperature reactor) and PBMR (Pebble Bed Moderated Reactor). These reactors are planned to operate at temperatures above 1000°C with neutron fluence up to 1022 cm-2. Accurate temperature measurement is needed to identify hot spots, control thermal cycles, and perform temperature compensation of other sensors; therefore, such measurements are critical to the safe operation of these reactors. This project will develop a drift-free fiber-optic-based temperature sensor, which will rely on the measurement of properties of stable materials to determine temperature. Commercial Applications and other Benefits as described by the awardee: Low-drift temperature measurement would enable the commercialization of Gen-IV reactor designs as well as increase safety in PWR (pressurized water reactors) and other Gen-III designs already in operation. Since the sensors will be radiation tolerant and high-temperature capable, the sensor also should find application in space probes, rocket engine monitoring, rocket engine development, and gas turbine health monitoring.