Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new calculation code opens new possibilities in nuclear reactor modelling

27.06.2007
Research Scientist Jaakko Leppänen from VTT Technical Research Centre of Finland has developed a new calculation code in his doctoral thesis, for the modelling of neutron physics in nuclear reactors. The so-called Monte Carlo method used by Leppänen has not been widely used for the production of input parameters for three-dimensional reactor simulator calculations.

The Monte Carlo method is a basic tool in particle transport problems, and it is well suited for tasks requiring the detailed modelling of geometry and physics. The method has been used in reactor physics calculations for decades, and the applications have mainly been restricted by computer capacity. In Leppänen's thesis, the use of the method is extended to new applications, when input parameters for three-dimensional reactor simulator calculations are generated using a Monte Carlo based lattice code.

Nuclear reactor modelling is a complicated task that combines neutron transport theory and the thermal hydraulics of coolant flow through the reactor core. Because of the complicated physics of neutron interactions, it is not possible to approach the problem as a single, well-defined task. Instead, the solution proceeds in steps, starting from the interactions between neutrons and the target nuclei. The intermediate step in the solution is the so-called lattice calculation, in which the geometry is modelled at the fuel assembly level. The results are then used as input parameters for a three-dimensional reactor simulator calculation, which yields the reactor response under different operating conditions.

The presently-used deterministic lattice codes have been developed mainly for the needs of light water reactor modelling, and the applications are not easily extended to advanced fuel types and next-generation reactor systems. Development in nuclear technology may hence require development in the calculation methods as well. A transition from deterministic to Monte Carlo lattice codes along with increasing computer capacity seems like a natural step in this respect. The use of a Monte Carlo based lattice code also brings all the advantages of the calculation method, and most importantly, the same code can be used for modelling any fuel or reactor type without compromising the reliability of the results.

The new calculation code developed at VTT is at first intended as a research tool, to be used in parallel with current deterministic lattice codes. The comparison of two codes based on entirely different calculation methods increases the reliability of the analyses, which is reflected in fuel management and reactor safety studies. The new code can also be used in studies involving next-generation reactor technology, in which the current deterministic lattice codes may not be applicable.

Research Scientist Jaakko Leppänen has defended his doctoral thesis at the Helsinki University of Technology on 18 June 2007 with the subject "Development of a New Monte Carlo Reactor Physics Code". The opponent in the defence was Associate Professor Eduard Hoogenboom from Delft University of Technology, the Netherlands.

Press Office | alfa
Further information:
http://www.vtt.fi/?lang=en

More articles from Physics and Astronomy:

nachricht New thruster design increases efficiency for future spaceflight
16.08.2017 | American Institute of Physics

nachricht Tracking a solar eruption through the solar system
16.08.2017 | American Geophysical Union

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>