Safety and Reliability of Nuclear Installations

Main directions of research, development of new safety methodologies

Development of new advanced methodologies corresponding to the current state of development (e.g. "best-estimate" approach based on the statistical evaluation of the evaluated results considering the uncertainties of the input data, computational models, correlations, uncertainties on NPPs, etc.);
Development and application of coupled versions of computer programs;
Development of advanced "Trade-off" methodologies for solution of safely operational restrictions;
Verification of safety acceptance criteria on experimental databases;
Validation of computational programs on experimental facilities;
Development and application of CFD computational programs for analysis of media behavior in circuits of nuclear power plant, containments and fuel assemblies;
Support planning and evaluation of thermohydraulic experiments;
Conceptual studies on nuclear safety.

Safety Analyses

"Best-estimate" analyses of the damage to the nuclear fuel cladding and evaluation of the fission product release to the coolant;
3D FEM modeling of fuel rods, respectively fuel assemblies;
Involvement in international programs organized by ECand OECD / NEA in the field of experimental research on fuel behavior in operational or DBA conditions.

Development of methodologies for advanced computational tools severe accidents;
Validation of integral computational tools (MELCOR, ASTEC, MAAP5-VVER) on experiments;
Development of own tools for processing input models based on graphical data;
Development of tools for evaluating the results of severe accident analysis for reactor applications and validation exercises;
Involvement in international research programs organized by the EC or OECD / NEA, and in OECD / NEA / ISP analytical exercises in many areas of severe accident phenomenology - eg. core degradation, hydrogen behavior, hydrogen deflagration, fission product behavior, evaluation of source terms, and minimization of uncertainties in the prediction of a severe accident.

Severe accidents and thermomechanics

Development of methodologies and tools in the field of radiation safety and emergency preparedness of nuclear power plants;
Development of tools for modeling the spread of radioactive substances to the environment and prediction of radiation effects;
Development of tools for modeling and visualization of the terrain radiation load and the assessment (prediction) of radiation doses to plant staff;
Development of 3D models of exteriors and interiors of the radiation source, visualization of the propagation of harmful substances into the environment;
Development of simulation tools and methods using virtual reality for planning and optimization of interventions in the NPP complex in case of a severe accident.
Radiation safety and preparedness
+420 266 172 446
Vladimir.Fiser@ujv.cz

Development of procedures for quantification of probabilistic parameters of risk assessment models for inadequate data, including application of Bayesian approache and use of expert judgment;
Monitoring the risk of nuclear and non-nuclear operations specifically focused on external events;
Development of methods of assessing the reliability of human in the conditions of the operation of complex technology under dynamically changing conditions;
Methods of collecting and evaluation of data from the training of the operators on full scope simulator;
Adaptation of probabilistic safety assessment methods to non-nuclear technologies;
Cost-benefit analyses methods for safety-enhancing applications;
Incorporaton if natural events into the risk models of complex technology;
Methodology of modeling and quantification of failure of digital information and control systems.

Reliability and risks - Jaroslav Holý

Adaptation of probability assessment methods of complex technology on reliability issues;
Reliable-oriented maintenance methodology (RCM);
Developing methods of assessing the reliability of a human within the conditions of the operation of complex technology under dynamically changing conditions;
Methodological support for analysis and estimation of probabilities of multiple faiulures with common cause;
Methodology of probability modeling of reliability of digital control and safety systems.

Reliability and risks - Jaroslav Holý

Development of tools for visualizing the results of severe accidents for the purpose of training of NPP staff
Development of virtual 3D models of nuclear power plant systems and components for staff training purposes
Development of virtual 3D models for decommissioning planning and optimization and dismantling practice of contaminated equipment

Division of Nuclear Safety and Reliability