Development of a fast 3D thermal-hydraulic tool for design and safety studies for HTRS Original Research Article

A three-dimensional thermal-hydraulic code called TH3D is being developed at the Institute of Nuclear Technology and Energy Systems (IKE), University of Stuttgart. The objective of this endeavor is to provide a tool which can be used to analyze, design, and safety related issues in high temperature reactors. The tool shall be generally applicable for modular HTRs. Operational conditions with forced cooling as well as accident situations with heat removal by conduction and natural circulation shall be covered. Coupling to a reactor physics code shall be provided to account for the feedback of neutronics and thermal-hydraulics. Emphasis is on capturing essential effects resulting from three-dimensional features (e.g. power distribution with block-type fuel elements) rather than on a high level of detail, in order to keep computation times reasonably low. In general, we strive for a quick-turn analysis that provides enough insight to make informed decisions that cannot wait for the extensive time it takes to conduct in-depth, detailed analyses, e.g. with large CFD models.