Modeling noise experiments performed at AKR-2 and CROCUS zero-power reactors
Artikel i vetenskaplig tidskrift, 2023

CORTEX is a EU H2020 project (2017-2021) devoted to the analysis of ’reactor neutron noise’ in nuclear reactors, i.e. the small fluctuations occurring around the stationary state due to external or internal disturbances in the core. One important aspect of CORTEX is the development of neutron noise simulation codes capable of modeling the spatial variations of the noise distribution in a reactor. In this paper we illustrate the validation activities concerning the comparison of the simulation results obtained by several noise simulation codes with respect to experimental data produced at the zero-power reactors AKR-2 (operated at TUD, Germany) and CROCUS (operated at EPFL, Switzerland). Both research reactors are modeled in the time and frequency domains, using transport or diffusion theory. Overall, the noise simulators managed to capture the main features of the neutron noise behavior observed in the experimental campaigns carried out in CROCUS and AKR-2, even though computational biases exist close to the region where the noise-inducing mechanical vibration was located (the so-called ”noise source”). In some of the experiments, it was possible to observe the spatial variation of the relative neutron noise, even relatively far from the noise source. This was achieved through reduced uncertainties using long measurements, the installation of numerous, robust and efficient detectors at a variety of positions in the near vicinity or inside the core, as well as new post-processing methods. For the numerical simulation tools, modeling the spatial variations of the neutron noise behavior in zero-power research reactors is an extremely challenging problem, because of the small magnitude of the noise field; and because deviations from a point-kinetics behavior are most visible in portions of the core that are especially difficult to be precisely represented by simulation codes, such as experimental channels. Nonetheless the limitations of the simulation tools reported in the paper were not an issue for the CORTEX project, as most of the computational biases are found close to the noise source.

Validation

CORTEX

Noise simulators

Experimental data

Författare

Mathieu Hursin

Paul Scherrer Institut

Ecole Polytechnique Federale de Lausanne (EPFL)

Andrea Zoia

Université Paris-Saclay

Amélie Rouchon

Université Paris-Saclay

A. Brighenti

Université Paris-Saclay

I. Zmijarevic

Université Paris-Saclay

S. Santandrea

Université Paris-Saclay

Paolo Vinai

Chalmers, Fysik, Subatomär, högenergi- och plasmafysik

Antonios Mylonakis

Chalmers, Fysik, Subatomär, högenergi- och plasmafysik

Huaiqian Yi

Chalmers, Fysik, Subatomär, högenergi- och plasmafysik

Christophe Demaziere

Chalmers, Fysik, Subatomär, högenergi- och plasmafysik

Vincent Lamirand

Ecole Polytechnique Federale de Lausanne (EPFL)

Paul Scherrer Institut

K. Ambrozic

Ecole Polytechnique Federale de Lausanne (EPFL)

T. Yamamoto

Kyoto University

S. Hübner

Technische Universität Dresden

A. Knospe

Technische Universität Dresden

Carsten Lange

Technische Universität Dresden

S. Yum

Technische Universität München

R. Macian

Technische Universität München

A. Vidal

Universitat Politecnica de Valencia (UPV)

Damian Ginestar

Universitat Politecnica de Valencia (UPV)

Gumersindo Verdu

Universitat Politecnica de Valencia (UPV)

Annals of Nuclear Energy

0306-4549 (ISSN) 1873-2100 (eISSN)

Vol. 194 110066

Core monitoring techniques and experimental validation and demonstration (CORTEX)

Europeiska kommissionen (EU) (EC/H2020/754316), 2017-09-01 -- 2021-08-31.

Styrkeområden

Energi

Ämneskategorier

Annan fysik

DOI

10.1016/j.anucene.2023.110066

Mer information

Senast uppdaterat

2023-09-23