TH-NK neutron noise analysis in KWU-PWR NPP

[EN] An increase in the magnitude of the acquired neutron noise has been recorded over several operating cycles in KWU-PWR reactors. This work forms part of a research that aims to improve the existing understanding regarding the phenomenology of neutron noise in these PWR reactors. The validation o...

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Detalles Bibliográficos
Autores: Olmo-Juan, Nicolás, Miró Herrero, Rafael|||0000-0003-1012-0869, Barrachina, Teresa|||0000-0001-8794-4204, Verdú Martín, Gumersindo Jesús|||0000-0001-5098-080X
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/225977
Acceso en línea:https://riunet.upv.es/handle/10251/225977
Access Level:acceso abierto
Palabra clave:Pressurized Water Reactor (PWR)
Kraftwerk Union AG (KWU)
Fluctuations
Neutron noise
Thermalhydraulics
Neutron kinetics
Sicherheitsventil Dampf (SVD)
Descripción
Sumario:[EN] An increase in the magnitude of the acquired neutron noise has been recorded over several operating cycles in KWU-PWR reactors. This work forms part of a research that aims to improve the existing understanding regarding the phenomenology of neutron noise in these PWR reactors. The validation of PARCS code to reproduce the neutron noise recorded in a real KWU reactor is presented. The methodology developed is based on the decomposition of the acquired signal by means of SVD analysis in order to obtain the temporal evolution and spatial distribution of the noise source. This perturbation is introduced as a disturbance in density in a TRACE/PARCS coupled simulation. In this way, the coupling with the TRACE code enables the ability to face, together, the feedback that occurs between the thermal-hydraulic and the neutronic fields. It was found that the transmission of the waves in the flow occurs instantaneously at all points while the temperature waves are transmitted with a phase lag. Because in the upper and lower signals of the real detectors, no phase shift between the two halves is observed, the main result is that the oscillations are related to disturbances in flow rate, or density, and not in temperature.