Computation of ex-core detector weighting functions for VVER-440 using MCNP5

Farkas, Gabriel; Lipka, J.; Haščík, Ján; Slugeň, V.

doi:10.1016/j.nucengdes.2013.01.026

Cited by 8 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figs. [6][7][8] show that the SAFs have a bottom-peaked shape because the two symmetric detectors were axially located just ~10 cm above the active core bottom (the length of excore detector is 40 cm whereas the active core height is ~82.144 cm). As is seen in those figures, the SAF at RCP slightly overestimates that at G1IN/G2IN/G3IN for the core axial position below RCP and vice versa for the core axial position above RCP.…”

Section: Resultsmentioning

confidence: 99%

“…In practice, the spatial weighting functions for the excore detectors can be generated using either the point kernel method [5], the discrete ordinate transport method [6], or the Monte Carlo method [7] [8]. It is noted that an advantage of the Monte Carlo method is the capability of modeling reactor configurations with arbitrary geometrical complexity.…”

Section: Calculation Methodologymentioning

confidence: 99%

“…For that reason, a dynamic rod worth simulation method applicable to SFRs needs to be developed and then applied to the BFS-76-1A for validating the measured control rod mockup worths. To simulate the pseudo excore detector signals needed for inferring the dynamic worth of control rods during the rod drop experiments, the excore detector spatial weighting functions which represent individual contributions from specific core locations, i.e., fuel assemblies, fuel rods or portions of rods, to the detector signal are required in advance [5][6][7][8]. It should be noted that the power regulation system of a fast reactor is based on the signals of excore neutron detectors.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Calculation of excore detector weighting functions for a sodium-cooled TRU burner mockup using MCNP5

Ha¹,

Min-Jae²,

Sunghwan³

et al. 2015

Nucl. Sci. and Tech.

View full text Add to dashboard Cite

Power regulation systems of fast reactors are based on the signals of excore detectors. The excore detector weighting functions, which establish correspondence between the core power distribution and detector signal, are very useful for detector response analyses, e.g., in rod drop experiments. This paper presents the calculation of the weighting functions for a TRU burner mockup of the Korean Prototype Generation-IV Sodium-cooled Fast Reactor (named BFS-76-1A) using the MCNP5 multi-group adjoint capability. For generation of the weighting functions, all fuel assemblies were considered and each of them was divided into ten horizontal layers. Then the weighting functions for individual fuel assembly horizontal layers, the assembly weighting functions, and the shape annealing functions at RCP (Reactor Critical Point) and at conditions under which a control rod group was fully inserted into the core while other control rods at RCP were determined and evaluated. The results indicate that the weighting functions can be considered relatively insensitive to the control rods position during the rod drop experiments and therefore those weighting values at RCP can be applied to the dynamic rod worth simulation for the BFS-76-1A.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Calculation Methodologymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Calculation of excore detector weighting functions for a sodium-cooled TRU burner mockup using MCNP5

Ha¹,

Min-Jae²,

Sunghwan³

et al. 2015

Nucl. Sci. and Tech.

View full text Add to dashboard Cite

show abstract

“…The reactivity determined by the inverse kinetic Equation ( 1) is typically considered the dynamic reactivity, which differs from the static reactivity. To remedy the difference between calculated static reactivity and measured dynamic reactivity, a dynamic reactivity correction is performed as follows: (17). In this research, the static reactivity is calculated using Monte Carlo N-Particle (MCNP) transport code [13] , and the neutron flux amplitude function is simulated transient analysis code for a pressurized water reactor at the Ulsan National Institute of Science and Technology and Xi'an Jiaotong University (TAPUX) [14] .…”

Section: Dynamic Reactivity Correctionmentioning

confidence: 99%

“… was determined. In this research, we focused on the integral rod worth; hence, the corresponding dynamic reactivity correction factor was calculated using Equation (17), and the results are listed in Table 2. The dynamic reactivity correction factors are close to 1, which means that the dynamic effect is small during the process.…”

Section: Correction Factor Calculationsmentioning

confidence: 99%

First application of large reactivity measurement through rod drop based on three-dimensional space–time dynamics

et al. 2021

View full text Add to dashboard Cite

Reactivity measurement is an essential part of a zero-power physics test, which is critical to reactor design and development. The rod drop experimental technique is used to measure the control rod worth in a zero-power physics test. The conventional rod drop experimental technique is limited by the spatial effect and the difference between the calculated static reactivity and measured dynamic reactivity; thus, the method must be improved. In this study, a modified rod drop experimental technique that constrains the detector neutron flux shape function based on three-dimensional space-time dynamics to reduce the reactivity perturbation and a new method for calculating the detector neutron flux shape function are proposed. Correction factors were determined using Monte Carlo N-Particle transport code and transient analysis code for a pressurized water reactor at the Ulsan National Institute of Science and Technology and Xi'an Jiaotong University, and a large reactivity of over 2000 pcm was measured using the modified technique. This research evaluated the modified technique accuracy, studied the influence of the correction factors on the modification, and investigated the effect of constraining the shape function on the reactivity perturbation reduction caused by the difference between the calculated neutron flux and true value, using the new method to calculate the shape function of the detector neutron flux and avoiding the neutron detector response function (weighting factor) calculation.

show abstract

A methodology for evaluating weighting functions using MCNP and its application to PWR ex-core analyses

Pecchia

Vasiliev

Ferroukhi

et al. 2017

Annals of Nuclear Energy

View full text Add to dashboard Cite

Computation of ex-core detector weighting functions for VVER-440 using MCNP5

Cited by 8 publications

References 4 publications

Calculation of excore detector weighting functions for a sodium-cooled TRU burner mockup using MCNP5

Calculation of excore detector weighting functions for a sodium-cooled TRU burner mockup using MCNP5

First application of large reactivity measurement through rod drop based on three-dimensional space–time dynamics

A methodology for evaluating weighting functions using MCNP and its application to PWR ex-core analyses

Contact Info

Product

Resources

About