NEET In-Pile Ultrasonic Sensor Enablement-Final Report

Abstract

Several programs funded by the Department of Energy Office of Nuclear Energy (DOE-NE), such as the Fuel Cycle Research and Development, Advanced Reactor Concepts, Light Water Reactor Sustainability, and Next Generation Nuclear Plant programs, are investigating new fuels and materials for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials during irradiation. The Nuclear Energy Enabling Technology (NEET) Advanced Sensors and Instrumentation (ASI) in-pile instrumentation development activities are focused upon addressing cross-cutting needs for DOE-NE irradiation testing by providing higher fidelity, real-time data, with increased accuracy and resolution from smaller, compact sensors that are less intrusive.Ultrasonic technologies offer the potential to measure a range of parameters during irradiation of fuels and materials, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes under harsh irradiation test conditions. There are two primary issues that currently limit in-pile deployment of ultrasonic sensors. The first is transducer survivability. The ability of ultrasonic transducer materials to maintain their useful properties during an irradiation must be demonstrated. The second issue is signal processing. Ultrasonic testing is typically performed in a lab or field environment, where the sensor and sample are accessible. The harsh nature of in-pile testing and the variety of desired measurements demand that an enhanced signal processing capability be developed to make in-pile ultrasonic sensors viable. To address these issues, the NEET ASI program funded a three year Ultrasonic Transducer Irradiation and Signal Processing Enhancements project, which was completed as a collaborative effort between the

Ultrasonic Al2O3 Ceramic Thermometry in High-Temperature Oxidation Environment

“…Acoustic impedance can be calculated as follows [7]: $Z=\frac{\rho c}{A}$ where ρ denotes material density, c indicates the velocity of sound, and A is the cross-sectional area of the acoustic waveguide. Based on ultrasonic impedance equation, we can deduce the ultrasonic reflection coefficient as follows [21,22]: $R=\frac{Z_2-Z_1}{Z_2+Z_1}$…”

“…In 2002, the Korea Atomic Energy Research Institute (Kil-MO Koo) used ultrasonic thermometry to measure core temperature in LAVA (Lower-Plenum Arrested Vessel Attack) at 2200 °C [5]. In 2010, the Idaho National Laboratory tested an improved, ultrasonic in-pile sensor for temperature detection during irradiation testing [6,7]. Experiments showed that UO 2 melting with an ultrasonic sensor embedded in a molten pool has a temperature near 3133 K, which is well in accordance with the expected value of 3123 K [8,9].…”

Multiphysics Finite Element Analysis of In-Pile Sensors for Advanced Nuclear Reactors

“…The major difference is magnetostrictive materials are actuated using coils and a magnetic field instead of a voltage applied to electrodes. This type of ultrasonic thermometer is being looked at by the INL for nuclear reactors due to its small size and ability to withstand high temperatures [2]. The small diameter wire also allows for dispersion of ultrasonic waves to be avoided [2].…”

“…This type of ultrasonic thermometer is being looked at by the INL for nuclear reactors due to its small size and ability to withstand high temperatures [2]. The small diameter wire also allows for dispersion of ultrasonic waves to be avoided [2]. INL tests have shown these sensors have increased accuracy when compared to other temperature sensing methods currently available [2].…”

“…The small diameter wire also allows for dispersion of ultrasonic waves to be avoided [2]. INL tests have shown these sensors have increased accuracy when compared to other temperature sensing methods currently available [2].…”