[PDF]    http://dx.doi.org/10.3952/lithjphys.47208

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 47, 211–219 (2007)


ANALYSIS OF IODINE RELEASE FROM THE DEFECTIVE FUEL ELEMENTS OF THE RBMK-1500 REACTOR
G. Klevinskas, L. Juodis, R. Plukienė, A. Plukis, and V. Remeikis
Institute of Physics, Savanorių 231, LT-02300 Vilnius, Lithuania
E-mail: jugintas@gmail.com

Received 27 April 2007; revised 25 May 2007

The results of modelling and analysis of iodine release to the main circulation circuit of the RBMK-1500 reactor are presented. General approach proposed by Lewis and Husain for the CANDU reactor primary coolant activity prediction was applied. Specific features of the RBMK-1500 coolant activity measurement were assessed. Non-stationary activity measurement conditions were identified and quantified with corresponding correction factors. Parameter values of the adapted model are comparable with those characteristic of CANDU reactor defective fuel.
Keywords: nuclear fuel, fission products, diffusion, radionuclide release mechanisms, iodine
PACS: 28.41.Kw, 83.80.-k


JODO IŠLAKŲ IŠ PAŽEISTŲ RBMK-1500 REAKTORIAUS KURO ELEMENTŲ ANALIZĖ
G. Klevinskas, L. Juodis, R. Plukienė, A. Plukis, V. Remeikis
Fizikos institutas, Vilnius, Lietuva

Branduolinio reaktoriaus darbo metu urano dioksido kuro tabletėse susidaro dalijimosi produktai (DP), kurie migruoja į tarpelį tarp kuro elemento tablečių ir cirkonio apvalkalo, o per pastarojo defektus patenka į reaktoriaus pagrindinio cirkuliacinio kontūro (PCK) vandenį. Prognozuoti DP sklaidą reaktoriaus kontūre yra svarbu, nes tai leidžia įvertinti avarijų pasekmes bei numatyti ilgalaikį radiacinį poveikį aplinkai ir gyventojams galutinai palaidojus eksploatacijos metu susidariusias DP užterštas radioaktyviąsias atliekas. Atsižvelgus į RBMK-1500 reaktoriaus PCK vandens aktyvumo matavimo specifiką, šiame darbe pateiktas papildytas DP balanso reaktoriaus pagrindiniame cirkuliaciniame kontūre modelis ir įvertintas radionuklidų koncentracijos kuro tarpelyje ir reaktoriaus pagrindiniame cirkuliaciniame kontūre kitimas kuro elemento cirkonio apvalkalo trūkio atveju bei pasiūlytos ir įvertintos atitinkamos radionuklidų koncentracijos pataisos. Išanalizuotas jodo izotopų išsiskyrimas iš kuro RBMK-1500 reaktoriaus atveju. Pateikiami jodo radionuklidų išlakų į RBMK-1500 reaktoriaus pagrindinį cirkuliacinį kontūrą modeliavimo ir analizės rezultatai. Apskaičiuoti jodo izotopų sklaidos RBMK-1500 reaktoriaus kontūre modelio parametrai ir efektinis jodo difuzijos koeficientas D′ RBMK-1500 reaktoriaus branduoliniame kure.


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