[EN] The simplified spherical harmonics equations are a useful approximation to the stationary neutron transport equation. The eigenvalue problem associated with them is a challenging problem from the computational point ...
[EN] Background: The respiratory epithelium is frequently infected by the respiratory syncytial virus, resulting in inflammation, a
reduction in cilia activity and an increase in the production of mucus.
Methods: In this ...
[EN] The early detection of anomalies through the analysis of the neutron noise recorded by in-core and ex-core instrumentation gives the possibility to take proper actions before such problems lead to safety concerns or ...
Carreño, Amanda; Vidal-Ferràndiz, Antoni; Ginestar Peiro, Damián; Verdú Martín, Gumersindo Jesús(International Center for Numerical Methods in Engineering (CIMNE), 2017-07-05)
[EN] High accuracy is required for the solution of the lambda modes problem associated with the
neutron diffusion equation. In this work, a multigrid method based on finite element method
has been proposed to solve this ...
[EN] Optical tomography has found many medical applications that need to know how the photons interact with the different tissues. The majority of the photon transport simulations are done using the diffusion approximation, ...
[EN] The mechanical vibrations of fuel assemblies have been shown to give rise to high levels of neutron noise, triggering in some circumstances the necessity to operate nuclear reactors at a reduced power level. This work ...
Carreño, Amanda; Vidal-Ferràndiz, Antoni; Ginestar Peiro, Damián; Verdú Martín, Gumersindo Jesús(R. Company, J. C. Cortés, L. Jódar and E. López-Navarro, 2019-07-12)
[EN] The solution of the time-dependent neutron diffusion equation can be approximated using quasi-static methods that factorise the neutronic flux as the product of a time dependent function times a shape function that ...
[EN] The distribution of the power inside a reactor core can be described by the time dependent multigroup neutron diffusion equation. One of the approaches to integrate this time-dependent equation is the modal method, ...
[EN] We develop and validate node homogenization methods, based on one and three-dimensional node equivalent problems, that improve the volume weighted method for the treatment of the rod cusping effect. The numerical ...
En este trabajo, se ha realizado un análisis de estabilidad en los puntos de operación
definidos en el bechmark de estabilidad de la central nuclear de Ringhals. Se quieren reproducir los
resultados obtenidos en el ...
García-Planells, Javier; Burguera, Juan A.; Solís, Pilar; Millán, José M.; Ginestar Peiro, Damián; Palau, Francesc; Espinós-Armero, Carmen Ángeles(John Wiley & Sons, 2005-05)
[EN] Huntington disease (HD) is an autosomal dominant neurodegenerative disorder characterized clinically by progressive motor impairment, cognitive decline, and emotional deterioration. The disease is caused by the abnormal ...
Coll Aliaga, Peregrina del Carmen; Sanabria Codesal, Esther; Ginestar Peiro, Damián; Sánchez Juan, Elena(Universitat Politècnica de València, 2017-05-15)
En este objeto de aprendizaje se le presenta al alumno aplicaciones de la transformada de Laplace a la resolución de ecuaciones diferenciales con condiciones iniciales. Se utiliza el programa Mathematica para realizar los ...
PL equations are classical approximations to the neutron transport equations, which are obtained expanding the angular neutron flux in terms of spherical harmonics. These approximations are useful to study the behavior of ...
González Pintor, Sebastián(Universitat Politècnica de València, 2012-11-16)
La ecuación de la difusión neutrónica describe la población de neutrones de un reactor nuclear. Este trabajo trata con este modelo para reactores nucleares con geometría hexagonal. En primer lugar se estudia la ecuación ...
Fayez Moustafa Moawad, Ragab(Universitat Politècnica de València, 2016-06-07)
[EN] The neutron diffusion equation is an approximation of the neutron transport equation that describes the neutron population in a nuclear reactor core. In particular, we will consider here VVER-type reactors which use ...
Lidón Cerezuela, Antonio Luis; Ramos Mompó, Carlos; Ginestar Peiro, Damián; Contreras Espinosa, Wilson Alberto(Elsevier Masson, 2013-04)
A simple compartmental model using a tipping bucket approach for the water dynamics coupled with a nitrogen¿carbon transformations model has been adapted to simulate the soil nitrogen and water balance in mature orange ...
[EN] The dominant lambda-modes associated with a nuclear reactor configuration describe the neutron steady-state distribution and its criticality. Furthermore, they are useful to develop modal methods to study reactor ...
[EN] In nuclear engineering, the lambda-modes associated with the neutron diffusion equation are applied to study the criticality of reactors and to develop modal methods for the transient analysis. The differential ...
Hueso-González, Fernando; Ginestar Peiro, Damián; Hueso Pagoaga, José Luís; Riera Guasp, Jaime(Institute of Electrical and Electronics Engineers, 2021-08-01)
[EN] The paper ¿SPICE Model of Photomultiplier Tube Under Different Bias Conditions¿ is commented. We revisit the mathematical formulation to compensate for some ambiguities in the original manuscript, and point out some ...