The Thermal-Hydraulic Out-of-Reactor Safety (THORS) is a large high-temperature sodium facility operated at Oak Ridge National Laboratory (ORNL) in the United States. A number of bundles simulating sodium-cooled fast reactor (SFR) cores were tested there. The measurements consist mostly of transient temperature fields in the wires and on the pin surfaces. Measurements of different pin/wires temperatures at several axial locations allow for reconstruction of the 3D temperature flow field. Pressure drop measurements over the entire test section, flow rates, and acoustic signals for boiling detection were also conducted.The benchmark was also part of the Expert Group on Reactor Core Thermal-Hydraulics and Mechanics (EGTHM) activities.
Created in 2019, under the guidance of the Working Party on Scientific Issues of Reactor Systems (WPRS) the expert group will perform specific tasks associated with core thermal-hydraulics aspects of present and future nuclear power systems.
The Working Group on the Analysis and Management of Accidents (WGAMA) is responsible for activities related to potential accidental situations in nuclear power plants, including the following technical areas: reactor coolant system thermal-hydraulics; design-basis accidents; pre-core melt conditions and progression of accidents and in-vessel phenomena; coolability of over-heated cores; ex-vessel corium interaction with coolant and structures; in-containment combustible gas generation, distribution and potential combustion; physical-chemical behaviour of radioactive species in the primary circuit and the containment; and source term. The activities mainly focus on existing reactors, but also have application for some advanced reactor designs. Priority setting is based on established CSNI criteria and in particular on safety significance and risk and uncertainty considerations.
The Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems (WPRS) studies the reactor physics, fuel performance, and radiation transport and shielding in present and future nuclear power systems.