Part IIA: New Reactor Systems and Methods
Part IIA covers multiphase flow topics of particular interest to the nuclear industry. Some of the most recently proposed advanced reactor designs and the main multiphase phenomena of importance to the nuclear industry are treated. The state-of-the-art and beyond in modelling and simulation methods (including CFD and CMFD applications) for core design and accident analysis is introduced. An article introducing Light Water Reactors will be e-mailed to the participants in Part IIA as tutorial material before the course.
Thursday (8:30-13:00 and 14:30-18:00)
13A. Introduction and multiphase phenomena in Design Basis Accidents
Introduction to thermal-hydraulics in reactor safety and historic developments. Loss-of-coolant accidents and reactor transients; their simulation and uncertainty evaluation. In-vessel accident phenomenology; modelling of core cooling.
14A. Advanced reactor concepts and phenomena
Review of advanced LWR concepts for near-term and Generation IV reactor development. Two-phase phenomena in passive safety systems (natural circulation, condensation, critical flow).
15A. Closure laws in nuclear systems codes
Development and validation of closure laws dependent on flow regime. Hydrodynamic and heat transfer closure relationships in system codes and their limitations. Predicting choked flow, stratified flow, CCFL.
16A. PIRT and Scaling methods for complex reactor transient analysis
Phenomena Identification Ranking Table (PIRT), Scaling analysis for integral test facilities (ITFs) design criteria, design of ITFs, use of system codes in scaling analysis, scaling analysis of PWR LOCAs and SBLOCAs, building integral and separate effect test validation matrices, code scalability conditions, uncertainty quantification.
17A. Instabilities in two-phase flow
Two-phase system instabilities. BWR Stability, stability maps, computational tools, practical applications.
Friday (8:30-12:30)
18A. Applications of two-phase RANS CFD models to complex nuclear safety problems
Computational thermal-hydraulics in the practice using a variety of modelling techniques for different problem configurations. From statistical average models to scale-resolving strategies. A brief review of CFD usage in the nuclear industry, including detailed modelling of a PWR, single-phase and two-phase flows in fuel bundles, critical discharge, pebble bed reactor, spent fuel transport and storage, and environmental flow around reactor buildings.
19A. Multiphase phenomena in Severe Accidents
Multiphase phenomena during severe accidents: vapour explosions, molten core quenching and coolability, etc. Severe accident codes; systems analyses and simulation.