Neutronic Calculations for Certain Americium Mixed Fuels and Clads in a Boiling Water Reactor

Frontiers in Energy Research ◽

10.3389/fenrg.2021.639416 ◽

2021 ◽

Vol 9 ◽

Author(s):

Mehtap Düz

Keyword(s):

Monte Carlo ◽

Spent Nuclear Fuel ◽

Reactor Core ◽

Nuclear Data ◽

Boiling Water ◽

Square Lattice ◽

Boiling Water Reactor ◽

Water Reactor ◽

Constant Pitch ◽

Nuclear Data Library

In this study, a Boiling Water Reactor (BWR) design was made using the Monte Carlo (MCNPX) method. The reactor core in the designed BWR system was divided into an 8 × 8 square lattice with a constant pitch of 30.48 cm. In this study, americium (Am), which is found in the minor actinidine (MA) of spent nuclear fuel known as nuclear waste from existing reactors, was used as fuel with the addition of oxygen and fluorine. In this study, AmO2 and AmF3 fuels at the rate of 0.02–0.1% were used as Americium Mixed Fuels, and Zircaloy-2 (Zr-2), SiC, and VC were used as clad. Neutronic calculations for certain Americium Mixed Fuels and clads were compared in the designed BWR system. In the BWR system designed in the study; keff, neutron flux, fission energy, heating, and depleted Am were calculated. The three-dimensional (3-D) modeling of the designed BWR system was performed by using MCNPX-2.7.0 Monte Carlo method and the ENDF/B-VII.0 nuclear data library.

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The effect of different fuels and clads on neutronic calculations in a boiling water reactor using the Monte Carlo method

Scientific Reports ◽

10.1038/s41598-020-79236-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mehtap Düz ◽

Selcan İnal

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Reactor Core ◽

Nuclear Data ◽

Boiling Water ◽

Square Lattice ◽

Boiling Water Reactor ◽

Water Reactor ◽

The Monte Carlo Method ◽

Nuclear Data Library

AbstractIn this study, a Boiling Water Reactor (BWR) modeling was done for the reactor core divided into square lattice 8 × 8 type using the Monte Carlo Method. Each of the square lattices in the reactor core was divided into small square lattices 7 × 7 type in groups of four. In the BWR designed in this study, modeling was made on fuel assemblies at pin-by-pin level by using neptunium mixed fuels as fuel rod, Zr-2 and SiC as fuel cladding, H2O as coolant. In fuel rods were used NpO2 and NpF4 fuels at the rate of 0.2%-1% as neptunium mixed fuels. In this study, the effect on the neutronic calculations as keff, neutron flux, fission energy, heating of NpO2 and NpF4 fuels in 0.2%-1% rates, and Zr-2 and SiC clads were investigated in the designed BWR system. The three-dimensional (3-D) modelling of the reactor core and fuel assembly into the designed BWR system was performed by using MCNPX-2.7.0 Monte Carlo method and the ENDF/B-VII.0 nuclear data library.

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Bounding Acoustic Load Development for Boiling Water Reactor Shroud and Shroud Supports

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2020-21633 ◽

2020 ◽

Author(s):

Matthew Walter ◽

Minghao Qin ◽

Daniel Sommerville

Keyword(s):

Pressure Vessel ◽

Reactor Core ◽

Reactor Pressure Vessel ◽

Boiling Water ◽

Boiling Water Reactor ◽

Water Reactor ◽

Structural Evaluation ◽

Loss Of Coolant Accident ◽

Specific Analysis ◽

Reactor Pressure

Abstract As part of the license basis of a nuclear boiling water reactor pressure vessel, a sudden loss of coolant accident (LOCA) event needs to be analyzed. One of the loads that results from this event is a sudden depressurization of the recirculation line. This leads to an acoustic wave that propagates through the reactor coolant and impacts several structures inside the reactor pressure vessel (RPV). The authors have previously published a PVP paper (PVP2015-45769) which provides a survey of LOCA acoustic loads on boiling water reactor core shrouds. Acoustic loads are required for structural evaluation of core shrouds; therefore, a defensible load is required. The previous research compiled plant-specific data that was available at the time. Since then, additional data has become available which will add to the robustness of the bounding load methodology that was developed. Investigations are also made regarding the shroud support to RPV weld, which was neglected from the previous study. This will allow a practitioner a convenient method to calculate bounding acoustic loads on all shroud and shroud support welds in the absence of a plant-specific analysis.

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