RANS based CFD methodology for a real scale 217-pin wire-wrapped fuel assembly of KAERI PGSFR

Applicability of RANS models and pressure drop in edge subchannels for 19-pin wire-wrapped fuel bundle channel in CiADS

“…The SST k-ω model slightly over-predicted the turbulence levels compared with the experimental data. This was probably because there are larger regions with smaller velocities [ 43 , 44 ]. However, this trend was far less pronounced than in the other turbulence models.…”

High-Fidelity Numerical Investigation on Elucidating Sodium Heat Transfer Characteristics for 37-Pin Wire-Wrapped Fuel Bundle in the PLANDTL Facility

“…However, the wire-wrapped fuel assembly has numerous contact lines and points between pins and wires, making the geometry complex and the computational mesh difficult to generate. This was accomplished using an innovative grid generation method using Fortran-based in-house code [3,4,8]. This grid generation methodology does not use the mesh generation utility of STAR-CCM+.…”

“…Because the actual wire shape is simulated without distorting the shape, a more accurate prediction of the contact area between the wire and the rod becomes possible. In the previous study, an innovative grid-based RANS methodology was applied to the CFX, and the pressure drop and heat transfer were well predicted [4,9]. The grid that forms around the rod and wire is referred to as the inner fluid domain.…”

“…In this study, RANS-based CFD calculations were performed the STAR-CCM+ simulation software to verify its ability to predict the heat transfer phenomena of the fuel assembly using the thermal data of the 37-pin wirewrapped fuel bundle of the PLANDTL facility. This CFD methodology is based on the innovative grid system developed in previous studies using Song's work on the experiment [3][4][5], and it is implemented with a Menter's shear stress transport (SST) turbulence model. The studies conducted in this thesis for the validation of the CFD methodology are as follows.…”

Investigation of pressure loss and velocity distribution in fuel assemblies with wire-wrapped rods by using RANS and LES with wall functions

“…The here reported overestimation of the pressure loss by using wall function overrates published results. Jeong et al (2017) have reported pressure loss for a 127-pins fuel assembly. RANS calculation with wall functions (k-ε) and wall resolved (SST k-ω) overestimate the experimentally determined pressure loss by about 10%.…”