Projects / Programmes
January 1, 2009
- December 31, 2014
| Code |
Science |
Field |
Subfield |
| 2.13.00 |
Engineering sciences and technologies |
Process engineering |
|
| 2.03.00 |
Engineering sciences and technologies |
Energy engineering |
|
| Code |
Science |
Field |
| T160 |
Technological sciences |
Nuclear engineering and technology |
| Code |
Science |
Field |
| 2.11 |
Engineering and Technology |
Other engineering and technologies |
nuclear engineering, safety analyses, design-basis accidents, severe accidents,thermal hydraulics, turbulent flow, boiling, water hammer, steam explosions, aerosols, atmosphere mixing,structural mechanics, ageing, micro-cracks,probabilistic safety assessment, reliability, genetic algorithms, human factor
Researchers (24)
Organisations (1)
| no. |
Code |
Research organisation |
City |
Registration number |
No. of publicationsNo. of publications |
| 1. |
0106 |
Jožef Stefan Institute |
Ljubljana |
5051606000 |
90,753 |
Abstract
The Reactor Engineering research programme includes basic and applied research in nuclear energy, engineering and safety. Phenomena that occur during transients, incidents and severe accidents in nuclear power plants are being investigated. Appart from contributing to the improvement of nuclear safety, research results are applicable to a wide range of industrial processes.
In the field of thermal-hydraulic safety research, the following basic phenomena that occur during design-basis accidents in light-water-reactor nuclear power plants are being investigated: heat transfer in single-phase and two-phase turbulent flow, subcooled nucleate boiling flow in vertical channels, as well as single-phase and two-phase water-hammer phenomena in piping systems. Basic phenomena which are specific to severe accidents are also being investigated: steam explosions due to interaction between coolant and molten reactor core, atmosphere mixing and stratification in the containment, steam condensation in the presence of non-condensable gases and aerosol behavior (transport, condensation and settling) in the containment. In addition, both design-basis and severe accidents are being modeled on integral scales using system computer codes.
In the field of structural safety research, new models are being developed to allow prediction of micro-damages and the study of their influence on the macroscopic behavior of materials. The investigations include simulations of initiation and growth of intergranular cracks in the random grain structure.
In the field of probabilistic safety assessment (PSA), new methods are being developed by including time as an additional dimension. PSA is integrated with optimization methods, such as simulated annealing. The influence of human factor on the reliability of complex technological systems is also being investigated.
Significance for science
HEAT AND MASS TRANSFER Simulations and development of boiling and critical heat flux models contribute to the development in the field of heat transfer and phase change in two-phase flows. Simulations of separated flow of liquid film and gas core in a vertical tube contribute to the research on flow pattern development in two-phase gas-liquid flow. Direct numerical simulations of turbulent heat transfer contribute to research on turbulence. Investigations of multiple jet impingement cooling contribute to the development of science in the field of heat transfer enhancement methods. Research in the field of numerical simulations of turbulent flows in fuel bundles constitutes a significant contribution in the field of fluid dynamics in complex geometries. The research of specific phenomena, included in research on the scale of plant systems, also contributes to science development. Research of phenomena, which were not taken into account earlier in simulations (such as multi-dimensional flow phenomena in the reactor vessel) are especially important. Simulations of thermal-hydraulic transient phenomena in the reactor cooling system on the system scale contribute to validation and improvements of two-phase flow models with heat and mass transfer. SEVERE ACCIDENTS Research on atmosphere mixing in the containment contribute to research in the field of buoyant flows. Research of hydrogen combustion is important for understanding the mechanisms of flame propagation. Research on steam explosions contributes to the understanding of mechanisms of core melt droplet solidification and breakup. STRUCTURAL SAFETY ANALYSES The development of multiscale simulation models is among the most active fields in material science and related disciplines. Our proposal of a complete procedure to automatically develop finite elements models of experimentally determined microstructures is among the first of a kind in the world. This also gives us a competitive edge for the development methods predicting the crack initiation and growth in realistic microstructures. The work is important for both nuclear safety and materials science in general. PROBABILISTIC SAFETY ASSESSMENT The research represents a contribution in the fields of probability theory and of the mathematical description of reliability of complex systems, based on the integration of the properties of individual components. The work is important for both nuclear safety and reliability science in general. An important scientific contribution is the development of new heuristic optimization algorithms and their application to real optimization problems.
Significance for the country
The results of all aspects and proposed fields of research and their mutual interrelation and complementarity form a theoretical basis for safety analyses, related with the safe and stable operation of the Krško nuclear power plant (NPP), as well as for the execution of expert tasks for the Krško NPP, the utility company GEN energy and the Slovenian Nuclear Safety Administration. The results thus directly and indirectly contribute to the level of the safety culture in Slovenia. Research in the fields of heat and mass transfer and severe accidents, including combined research with structural integrity and probabilistic safety analyses, are especially important for interdisciplinary analyses and expert tasks that involve transient phenomena and hypothetical accidents. In this way, the research contributes to the long-term availability of competitive electrical energy, and to the protection of the population and the environment. Research in the field of structural integrity and ageing enables a more accurate prediction of the lifetime of important components of the Krško NPP, which has a direct influence on the availability of electricity. Research in the field of probabilistic safety assessment and risk contributes to the establishment of risk-informed decision-making and accelerates the development of regulations and standards based on risk analyses. The purposes of all research activities are set to enable direct knowledge transfer in support of the life-time extension of the existing plant and the planned construction of a new nuclear plant in Slovenia. The importance of research in the general field of nuclear safety (which is also relevant for Slovenia) has especially been shown by the accident at the Fukushima nuclear power plant in Japan (March-April 2011), where it was confirmed, that the prediction of the further course of an accident is important for adequate mitigation and limiting of the consequences. The research programme is also related to the 2nd degree University studies program “Nuclear engineering” and to the Doctoral studies program “Nuclear engineering”, both at the Faculty of Mathematics and Physics at the University of Ljubljana. This allows the transmission of knowledge to next generations and the education of new experts.
Audiovisual sources (1)
| no. |
Title (with video link) |
Event |
Source |
| 1. |
Reactor engineering |
Promotional video of research programme on Videolectures |
Research programme video presentation
|
Most important scientific results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
