Semi-analytical modeling of the flow redistribution upstream from the mixing grids in a context of nuclear fuel assembly bow

Numerical investigation on effects of fuel rod with different shapes of bow deformation on the subcooled boiling of coolant in a fuel assembly

“…According to the relevant literature, the proportion of coolant flow into different subchannels is highly dependent on the width of the clearance. [25,47] In this paper, the relative thermodynamic parameters in the study of subcooled boiling of fuel assemblies are compared and analyzed. The effects of different shapes of bow deformation of fuel rod on thermodynamic properties of coolant are obtained.…”

“…Horváth and Dressel [ 17 ] used CFD to study the flow redistribution at the outlet caused by bow deformation of fuel rods, and results showed that the pattern of bow deformation had an impact on flow distribution in the bowing region. de Lambert et al [ 25 ] chose a 1D convergent‐diffuser channel model to represent fuel assembly, and its thickness could be changed to reflect the bow deformation of fuel assembly. They found that the change of water gap width had an obvious effect on the flow redistribution and mean velocity of coolant in the subchannels.…”

A new reduced order model to represent the creep induced fuel assembly bow in PWR cores

“…Table 6 gives the different profiles LAT1 to LAT9 defined to study the response of the FA under lateral loading. LAT1, LAT2, LAT3 and LAT5 are realistic sets of forces coming from hydraulic simulations (De Lambert et al, 2021). LAT4 figures a contact force at mid height without hydraulic lateral forces.…”

Effect of stochastic deformation on the vibration characteristics of a tube bundle in axial flow

“…Peculiar about deformations is that they are (quantitatively) rather unpredictable (Wanninger et al, 2018) due to the complex environment and a multiplicity of causes and influences (Boltax et al, 1978;Sosnovsky et al, 2015;Roelofs et al, 2019;de Lambert et al, 2021;Leturcq et al, 2022), such as spatial distribution of coolant temperature and irradiation dose, material properties, fuel residence time and power cycle history (Bottcher and Hofman, 1977;Sakai et al, 1978). Especially deflection amplitude and direction were found to be sensitive to uncertain parameters (Wanninger et al, 2018).…”