Accelerated irradiation testing and post-irradiation characterization: U.S.-based capabilities for advanced nuclear systems and radioisotope production

Irradiation experiments and post-irradiation examinations (PIE)—together referred to as “Irradiation Testing” IRT—are prerequisites for nuclear fuel and material qualification for the deployment of new and advanced reactors, as well as radioisotope production, thereby ensuring regulatory compliance. Qualified research and test reactors (RTRs) and testing facilities are essential to enable IRT to verify performance and safety […]

Influence of Joule Heating on the Stability of High Temperature Irradiation Resistant Thermocouples

Development of in-core instrumentation is driven by the pursuit of safer and more economic energy production from both existing nuclear reactors and Generation IV reactor designs. Idaho National Laboratory (INL) has developed high temperature irradiation resistant thermocouples (HTIR-TCs) for temperature sensing inside Generation IV nuclear reactors. These thermocouples are composed of phosphorus-doped niobium (Nb-P) and […]

High-temperature irradiation-resistant thermocouple instability model for in-pile reactor use

This article presents an instability model for the high-temperature irradiation resistant thermocouple (HTIR-TC). Here the term instability defines the superposition of both drift and inhomogeneity of TC thermoelements occurring simultaneously. The HTIR-TC is an advanced thermocouple (TC) that uses the refractory metals niobium and molybdenum as sensing thermoelements for generating electromotive force (EMF) in a […]

Function and Operational Requirements for High Temperature Irradiation Resistant Thermocouples

The function and operation requirements for the High Temperature Irradiation Resistant Thermocouple are set forth. A mission and product are proposed. The function and operational requirements involve temperature range, accuracy, drift, life, mechanical ruggedness, and response time. Each have a criterion set to establish a thermocouple that can withstand a typical 18-month nuclear power plant […]

Development and Test Results of Thermocouples Used in the TRISO-Fuel Irradiation Experiment AGR-5/6/7

High-temperature gas reactor experiments create unique challenges for thermocouple-based temperature measurements. High-temperature industrial thermocouples suffer rapid decalibration due to transmutation of the thermoelements from neutron absorption. For lower temperature applications, Type K and Type N thermocouples are affected by neutron irradiation only to a limited extent. But until recently, the use of these nickel-based thermocouples […]

High Temperature Irradiation Resistant Thermocouple Qualification Test Results Report

This is a qualification report for the high-temperature irradiation-resistant thermocouple (HTIR-TC) developed by Nuclear Energy Enabling Technologies Advanced Sensors and Instrumentation program. Utilizing the Advanced Gas Reactor (AGR) 5/6/7 test conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory, the HTIR-TCs measured temperatures upwards of 1500°C during accident conditions. The HTIR TCs are […]