Dynamic Monte Carlo Method for Nuclear Reactor Kinetics Calculations

Sjenitzer, Bart L.; Hoogenboom, J. Eduard

doi:10.13182/nse12-44

Cited by 78 publications

(15 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The time evolution of neutron histories is followed directly rather than by a set of quasi-static calculations in consecutive time steps. The GUARDYAN calculation flow has many similarities to the DMC methodology proposed and developed in [1,2] with many of the techniques revised and adjusted to better fit the GPU architecture. These include the time step methodology instead of the classical generation-to-generation tracking, the improved branchless method [18] preventing history branching and thus banishing large particle banks, and the forced decay of precursors ensuring that prompt fission chains are never undersampled.…”

Section: Benchmark Modelmentioning

confidence: 99%

“…The computational capacity of the modern high-performance computing systems allows for more and more detailed calculation of reactor kinetics involving spatial effects in high temporal resolution, which are beyond the validity of point-kinetics or quasi-static approximations. Besides the improved deterministic transport approximations (e.g., S N or P L methods), promising developments were also reported recently in the field of Monte Carlo reactor kinetics calculations [1][2][3][4]. Validated spatial-kinetics calculation tools can significantly contribute Focus Point on Advances in the physics and thermohydraulics of nuclear reactors edited by J. Ongena, P. Ravetto, M. Ripani, P Saracco.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Simulation of a research reactor reactivity transient with deterministic and GPU-assisted Monte Carlo reactor kinetics codes

et al. 2020

View full text Add to dashboard Cite

Reactor kinetic codes are crucial in safety assessment. Validating spatial and high temporal resolution kinetic solvers without thermal feedback is problematic as measurements seldom involve detailed spatial and fine temporal resolution. Benchmarking of deterministic codes thus often resorts to code-to-code comparison against Monte Carlo codes, which can only recently treat direct time dependence. In this paper, we have attempted to compare results from the GUARDYAN directly time-dependent Monte Carlo code and the SEnTRi transient driver developed for the PARTISN deterministic transport code to low power transient measured at the BME Training Reactor. Code-to-measurement comparisons were successful, despite a major uncertainty in the actual timing of the reactivity insertion and withdrawal originating from the instrumentation of the pneumatic rabbit system. Code-to-code comparisons concluded that time dependence was correctly implemented in both GUARDYAN and SEnTRi; furthermore, a hypothetical scenario was set up involving an instantaneous insertion of a negative reactivity into the BME TR core in order to compare spatially and temporally dependent fluxes. The simulations demonstrated the appearance of higher-order modes, and results showed a relatively good match, although fidelity of the comparison could be further improved by reducing the statistical uncertainty of the results provided by GUARDYAN.

show abstract

Section: Benchmark Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Simulation of a research reactor reactivity transient with deterministic and GPU-assisted Monte Carlo reactor kinetics codes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The Monte Carlo approximation has been recently proposed to solve the time-dependent neutron transport equation [22,23,24,25], handling the time variation of the neutron flux updating event times during the Monte Carlo neutron tracking.…”

Section: Introductionmentioning

confidence: 99%

Validation of the SHNC time-dependent transport code based on the spherical harmonics method for complex nuclear fuel assemblies

Capilla

Talavera

Ginestar

et al. 2020

Journal of Computational and Applied Mathematics

View full text Add to dashboard Cite

The diffusion approximation to the time-dependent Boltzmann transport equation gives accurate results for traditional nuclear reactor designs, but new reactor designs and new fuel elements require neutron transport methods. We develop a numerical approximation to the time-dependent transport equation coupled to delayed neutron precursors based on the spherical harmonics P L equations, for odd L, and on the Backward Euler finite difference discretization of time. The resulting scheme can be written as a stationary form of diffusive second order P L equations. This allows a reduction by half to the number of unknowns and also to apply a nodal collocation method to the spatial discretization of the problem, using coarse spatial grids to further reduce memory requirements. This scheme is validated with several transient benchmarks, where the convergence properties are established and compared with the simplified P L approximation. A more realistic transient benchmark, based on the two-group C5 MOX problem, is finally introduced, showing the need of high order P L approximation for complex fuel geometries.

show abstract

“…The objective of this paper is to devise a simple but practical way to determine an optimum detector position for the measurement through the PNS experiment using the time-dependent Monte Carlo (TDMC) neutron transport analyses [17][18][19]. In the TDMC calculations, the combing algorithm [17,20] is applied to maintain the time-bin-wise neutron population because an exponential decrease of the neutron population in an analog TDMC calculation of a subcritical system causes large statistical uncertainties.…”

Section: Introductionmentioning

confidence: 99%

Determination of an Effective Detector Position for Pulsed-Neutron-Source Alpha Measurement by Time-Dependent Monte Carlo Neutron Transport Simulations

Jang

Shim

2018

Science and Technology of Nuclear Installations

View full text Add to dashboard Cite

A simple method using the time-dependent Monte Carlo (TDMC) neutron transport calculation is presented to determine an effective detector position for the prompt neutron decay constant (α) measurement through the pulsed-neutron-source (PNS) experiment. In the proposed method, the optimum detector position is searched by comparing amplitudes of detector signals at different positions when their α estimates by the slope fitting are converged. The developed method is applied to the Pb-Bi-zoned ADS experimental benchmark at Kyoto University Critical Assembly. The α convergence time estimated by the TDMC PNS simulation agrees well with the experimental results. The α convergence time map and the corresponding signal amplitude map predicted by the developed method show that polyethylene moderator regions adjacent to fuel region are better positions than other candidates for the PNS α measurement.

show abstract

Dynamic Monte Carlo Method for Nuclear Reactor Kinetics Calculations

Cited by 78 publications

References 22 publications

Simulation of a research reactor reactivity transient with deterministic and GPU-assisted Monte Carlo reactor kinetics codes

Simulation of a research reactor reactivity transient with deterministic and GPU-assisted Monte Carlo reactor kinetics codes

Validation of the SHNC time-dependent transport code based on the spherical harmonics method for complex nuclear fuel assemblies

Determination of an Effective Detector Position for Pulsed-Neutron-Source Alpha Measurement by Time-Dependent Monte Carlo Neutron Transport Simulations

Contact Info

Product

Resources

About