Search for dissertations about: "Florian Fichot"

Showing result 1 - 5 of 6 swedish dissertations containing the words Florian Fichot.

2. 1. Particulate Debris Spreading and Coolability

   Author : Simone Basso; Pavel Kudinov; Florian Fichot; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Self-leveling; debris bed; spreading; coolability; severe accident; probabilistic framework; Monte Carlo; uncertainty; sensitivity; Fysik; Physics;

   Abstract : In Nordic design of boiling water reactors, a deep water pool under the reactor vessel is employed for the core melt fragmentation and the long term cooling of decay heated corium debris in case of a severe accident. To assess the effectiveness of such accident management strategy the Risk-Oriented Accident Analysis Methodology has been proposed. READ MORE

4. 2. Numerical Investigations on Debris Bed Coolability and Mitigation Measures in Nordic Boiling Water Reactors

   Author : Zheng Huang; Weimin Ma; Florian Fichot; KTH; []
   Keywords : Severe accident; Debris bed; Coolability; Quench; Oxidation; MEWA code; Coupled analysis; Svåra haverier; Grusbädd; Kylbarhet; Kylning; Oxidering; MEWA program; Kopplad analys; Physics; Fysik;

   Abstract : This thesis is aiming at coolability assessment of particulate debris beds formed in hypothetical severe accidents of Nordic boiling water reactors (BWRs) which may employ either lower drywell flooding or control rod guide tubes (CRGT) cooling as severe accident management strategies. For this purpose, quench and cooling limit (dryout) of debris beds after their formation from fuel coolant interactions were investigated by numerical simulations using the MEWA code. READ MORE

5. 3. On Fuel Coolant Interactions and Debris Coolability in Light Water Reactors

   Author : Sachin Thakre; Weimin Ma; Florian Fichot; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; severe accident; fuel-coolant interactions; melt jet fragmentation; steam explosion; debris bed coolability; uncertainty analysis; Energiteknik; Energy Technology;

   Abstract : During the case of a hypothetical severe accident in a light water reactor, core damage may occur and molten fuel may interact with water resulting in explosive interactions. A Fuel-Coolant Interactions (FCI) consists of many complex phenomena whose characteristics determine the energetics of the interactions. READ MORE

6. 4. Development, validation and application of an effective convectivity model for simulation of melt pool heat transfer in a light water reactor lower head

   Author : Chi Thanh Tran; Truc-Nam Dinh; Florian Fichot; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; light water reactor; hypothetical severe accident; accident progression; accident scenario; core melt pool; heat transfer; turbulent natural convection; heat transfer coefficient; phase change; mushy zone; crust; lower plenum; analytical model; effective convectivity model; CFD simulation.; Other physics; Övrig fysik;

   Abstract : Severe accidents in a Light Water Reactor (LWR) have been a subject of the research for the last three decades. The research in this area aims to further understanding of the inherent physical phenomena and reduce the uncertainties surrounding their quantification, with the ultimate goal of developing models that can be applied to safety analysis of nuclear reactors. READ MORE

7. 5. Development and Application of Uncertainty Analysis Approaches for MELCOR Simulations of Severe Accidents

   Author : Wanhong Wang; Weimin Ma; Florian Fichot; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Severe accident; MELCOR; uncertainty analysis; Wilks’ method; Bootstrapped artificial neural network; deterministic sampling method; 95 95 tolerance limit.; Svåra haverier; MELCOR; osäkerhetsanalys; Wilks’ metod; artificiella neuronnät; deterministiska urvalsmetoder; 95 95-toleransgränser.;

   Abstract : The contemporary needs in advancing safety analysis methods and the increasing stringency in light water reactor (LWR) safety in the post-Fukushima era require more advanced and systematical approaches for severe accident analyses. The best estimate plus uncertainty (BEPU) methods are among such approaches and have been widely used for deterministic safety analysis (DSA) of design basis accidents (DBAs). READ MORE