Development and validation of a multi-scale and multi-physics methodology for the safety analysis of fast transients in Light Water Reactors

Abstract

Deferred neutron precursor fraction of the k-group (non-dimensional) Σ , Macroscopic transport cross section of energy group (cm -1 ) Σ , ⟶ ′ Macroscopic scattering cross section of energy group to ′ (cm -1 ) Σ , Macroscopic fission cross section of energy group (cm -1 ) Σ , Macroscopic absorption cross section of energy group (cm -1 ) Volumetric force tensor applied to the k-phase of a multiphase fluid (N/m 3 ) Deferred neutron decay constant of the precursor group (s -1 ) Dynamic Viscosity (Pa-s) Average Neutrons Emitted by fission (non-dimensional) Density (kg/m 3 ) Density of the -phase of a multiphase fluid (kg/m 3 ) Neutron Flux for energy group (neutrons/cm 2 ) Fission spectrum of the neutrons of the energy group Cross section area (m 2 ) ⃗ Area Vector (m 2 ) Drag coefficient (non-dimensional) Specific Heat Capacity of the fuel pellet (J/kg-K) Concentration of delayed neutron precursors of the -group (neutrons/cm 3 ) Neutron diffusion constant of the energy group (cm -1 ) Conservation of energy Gravity acceleration (m/s 2 ) ℎ Fuel Pellet Enthalpy (J/kg). Velocity Scalar Component parallel to axis (m/s) V Volume (m 3 ) Velocity Scalar Component parallel to axis (m/s) Mean neutron velocity of the neutrons in the energy group (cm/s) Work per volume unit (J/m 3 ) Velocity Scalar Component parallel to axis (m/s)To all the workers of the Scientific Research Field, that with his compromise struggle to make of this profession a dignified one.