On the influence of biological shielding on neutron flux behind reactor pressure vessel

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F26722445%3A_____%2F18%3AN0000168" target="_blank" >RIV/26722445:_____/18:N0000168 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.astm.org/DIGITAL_LIBRARY/STP/PAGES/STP160820170079.htm" target="_blank" >https://www.astm.org/DIGITAL_LIBRARY/STP/PAGES/STP160820170079.htm</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1520/STP160820170079" target="_blank" >10.1520/STP160820170079</a>

Jazyk výsledku

angličtina

Název v původním jazyce

On the influence of biological shielding on neutron flux behind reactor pressure vessel

Popis výsledku v původním jazyce

The neutron flux behind the reactor pressure vessel (RPV) is formed by primary transmitted neutrons from the core and also by backscattered neutrons from biological shielding. In the evaluations of neutron flux in the RPV, the knowledge of the reflected neutrons' share on the total flux is important for correct assessment of possible discrepancies. This paper aims to determine the share of backscattered neutrons in the spectrum behind the RPV and presents new results obtained with an improved fixed source model based on more precise and validated power distribution. Measurements of fast and thermal neutron fluxes in various configurations of biological shielding are realized in a VVER-1000 mock-up in the LR-0 reactor. Additionally, the calculations of the VVER-1000 mock-up are supplemented by calculations of an Electricite de France heavy reflector benchmark that represents arbitrary pressurized water reactor geometry. Comparison of both types of results shows that the LR-0 mock-up measurements are directly applicable, in terms of reactor dosimetry, to other types of pressurized water reactors, regardless of the burn-up and type of fuel they use. It is shown that the amount of backscattered thermal neutrons behind the reactor vessel strongly depends on the distance between the vessel and the concrete shielding. The choice of the data library for calculations influences the results in the thermal region as well.

Název v anglickém jazyce

On the influence of biological shielding on neutron flux behind reactor pressure vessel

Popis výsledku anglicky

The neutron flux behind the reactor pressure vessel (RPV) is formed by primary transmitted neutrons from the core and also by backscattered neutrons from biological shielding. In the evaluations of neutron flux in the RPV, the knowledge of the reflected neutrons' share on the total flux is important for correct assessment of possible discrepancies. This paper aims to determine the share of backscattered neutrons in the spectrum behind the RPV and presents new results obtained with an improved fixed source model based on more precise and validated power distribution. Measurements of fast and thermal neutron fluxes in various configurations of biological shielding are realized in a VVER-1000 mock-up in the LR-0 reactor. Additionally, the calculations of the VVER-1000 mock-up are supplemented by calculations of an Electricite de France heavy reflector benchmark that represents arbitrary pressurized water reactor geometry. Comparison of both types of results shows that the LR-0 mock-up measurements are directly applicable, in terms of reactor dosimetry, to other types of pressurized water reactors, regardless of the burn-up and type of fuel they use. It is shown that the amount of backscattered thermal neutrons behind the reactor vessel strongly depends on the distance between the vessel and the concrete shielding. The choice of the data library for calculations influences the results in the thermal region as well.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20305 - Nuclear related engineering; (nuclear physics to be 1.3);

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název statě ve sborníku

ASTM Special Technical Publication Volume STP 1608, 2018

ISBN

978-080317661-4

ISSN

0066-0558

e-ISSN

—

Počet stran výsledku

13

Strana od-do

308-320

Název nakladatele

ASTM International

Místo vydání

—

Místo konání akce

Santa Fe, USA

Datum konání akce

12. 5. 2017

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

—