Lattice code choice effect and geometry and material uncertainties in core physics calculations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F46356088%3A_____%2F16%3AN0000028" target="_blank" >RIV/46356088:_____/16:N0000028 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Lattice code choice effect and geometry and material uncertainties in core physics calculations

Original language description

Full-core calculations often show significant differences from the measured reactor records and one of the most important questions is whether the difference is caused mostly by a methodology bias of the computation stack (basic nuclear data-lattice code model-lattice code-XS homogenization-XS parameterization-core physics code) or rather by inherent input data uncertainties. In other words: can we improve the agreement between calculation and measurement by improving our methods or are the observed differences below the effect of the uncertainties? In this paper we focus on the influence of material and geometry uncertainties. We use Monte-Carlo sampling approach: various parameters of the fuel assemblies (dimensions, enrichment etc.) have uncertainties or tolerances attached and we run hundreds of lattice code calculations and generate a large amount of macroscopic XS libraries. Afterwards, a sampling mechanism is used to run hundreds of full-core core physics calculations; the results are then gathered and statistically processed. In the end we obtain full-core results (critical boric acid concentration, peaking factors, spatial power distribution) with resulting uncertainties attached. This paper presents the methods we have used and the results obtained so far: impact of aforementioned factors on principal neutron-physical core characteristics (reactivity, power distribution, feedback coefficients) is quantified and evaluated.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

JF - Nuclear energy

OECD FORD branch

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Project

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Continuities

N - Vyzkumna aktivita podporovana z neverejnych zdroju

Publication year

2016

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

International Congress on Advances in Nuclear Power Plants, ICAPP 2016 Volume 1, 2016

ISBN

978-151082594-9

ISSN

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e-ISSN

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Number of pages

9

Pages from-to

603-611

Publisher name

American Nuclear Society

Place of publication

La Grange Park, Illinois, USA

Event location

San Francisco, USA

Event date

Apr 17, 2016

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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