MCNP and ORIGEN codes validation by calculating RBMK spent nuclear fuel isotopic composition

Abstract

Benchmark calculations of RBMK reactor spent nuclear fuel isotopic composition were performed using the MCNP and ORIGEN codes system. The RBMK assembly is explicitly modelled in order to investigate the differences of spent nuclear fuel burn-up due to different coolant density and the fuel rod position (inner or outer ring in the assembly). The modelling results are compared with experimentally measured data of RBMK-1000 fuel isotopic composition with 2% enrichment 235 U fuel at different fuel burn-up. The comparison of the experimentally measured and calculated isotopic composition for the main actinides and fission products allowed validation of MCNP and ORIGEN codes for RBMK spent nuclear fuel calculations. Variations of RBMK spent nuclear fuel burn-up and plutonium isotopic ratios depending on fuel location in the assembly were determined.

On the activity ratio90Sr/137Cs in soil of the Chernobyl Nuclear Power Plant 30-km zone in Ukraine

“…In this connection in our study one of the most possible reasons for the underestimation of the total content of 90 Sr, Q( 90 Sr) ∼ 1.25·10 15 Bq, in the 30-km zone of the ChNPP in Ukraine in works [1,2] in comparison with the commonly accepted estimation of the total content Q( 90 Sr) ∼ 3·10 15 Bq is considered.…”

“…Underestimation of the total content of 90 Sr, Q( 90 Sr) ∼ 1.25·10 15 Bq, in [1,2] is the result of the error of calculation technique. Thus, at one of the stages of experimental data processing in [1,2] the arithmetic mean is replaced by the harmonic mean for the density of soil contamination ratio A( 90 Sr)/A( 137 Cs).…”

“…All these facts can actually explain qualitatively the underestimation of the total content of 90 Sr, Q( 90 Sr) ≈ 1.25·10 15 Bq, obtained in [1] according to Eq. (3), in comparison with the commonly accepted value ∼3·10 15 Bq in soil of the 30-km zone of the ChNPP in Ukraine.…”

“…(3), in comparison with the commonly accepted value ∼3·10 15 Bq in soil of the 30-km zone of the ChNPP in Ukraine.…”

generation of RBMK-1500 spent nuclear fuel one-group cross-section libraries and their evaluation against experimental data

“…The SNF composition determination using direct or indirect experimental techniques is rather expensive and technically complicated. Therefore, computer modelling is often used to evaluate SNF characteristics [2][3][4]. However, validation of these results is also essential: results of calculations of various complexity should correspond to available experimental knowledge [5][6][7].…”