Dynamic Coefficients Identification Using the POD Method

Earthquakes can irreversibly damage nuclear power plants especially in the core. Engineers need special tools to insure that the core will resist the worst conditions. Most of the models developed for industrial purpose account for the damping and added mass induced by the axial flow, and need to identify the related coefficients. Therefore, experiments on full scale fuel assemblies need to be performed. The LHC (Laboratory of Core and Circuit Hydrodynamics) has facilities to perform dynamical tests under axial flow of a fuel assembly. The displacement of one grid of the fuel assembly is imposed by a hydraulic jack with a force sensor, and the displacements of the other grids are measured. LDV measurements are also performed to give a description of the flow distribution in the fuel assembly. An identification based on a Proper Orthogonal Decomposition is proposed. Co-efficients obtained are given by unit of length, which means that they are directly available for models.Copyright © 2013 by ASME