Numerical Computation of Heat Transfer Enhancement of a PWR Rod Bundle with Mixing Vane Spacers

Evaluation of a numeric procedure for flow simulation of a 5 × 5 PWR rod bundle with a mixing vane spacer

“…In CFX 11.0 [18] the k-ε model uses a scalable wall-function approach to limit a lower value for the dimensionless distance from the wall used in the log-law.…”

“…Amongst the many studies performed involving CFD simulations of rod bundles with spacer grids some with the most significant contributions are: Karoutas et al [9] and Imaizumi et al [10] that demonstrated the usefulness of single subchannel CFD (Computational Fluid Dynamic) methodologies coupled with experimental results from LDV and pressure loss measurements on the development of fuel designs for PWR reactors; In et al [11] that enhanced the numerical methodology of Karoutas et al [9]; Ikeda and Hoshi [12] that performed 5x5 partial grid CFD simulations that showed comparable results to experimental pressure loss, cross-flow and DNB (Departure from Nucleate Boiling) measurements on freon flow passing through a grid with mixing vanes; Single subchannel numerical simulations of Cui and Kim [13], Kim and Seo [14,15] and Haixiang and Ping [16] that optimized mixing vane shape and showed their theoretical effect on the flow structure; Simulations performed by Lee and Choi [17] that examined turbulence characteristics of flow downstream four different spacers and showed that the number of subchannels in a CFD model is important for accurate predictions due to the complex exchange between subchannels; And In et al [18] that performed a series of four subchannels CFD simulations to analyze the heat transfer enhancement in a fully heated rod bundle with vaned spacers.…”

Challenge Analysis and Schemes Design for the CFD Simulation of PWR

“…CFD simulation of a reactor is an important part for the development of NVR because CFD simulation can reflect the detailed flow and heat transfer which can be used in the further application or research. For instance, with the application of CFD simulation, In et al [5] analyzed the principle of heat transfer enhanced by spacer grid with mixing vane, Kim and Seo [6,7] gave the optimal design of the shape of mixing vane, Lee and Choi [8] study the influence of the region size of the research object, and so on. Though CFD simulation is so important, some challenges still exist in the application.…”

Influence of Spacer Grid Outer Strap on Fuel Assembly Thermal Hydraulic Performance

“…Holloway et al showed that there was a great variation of heat transfer distribution along a fuel rod due to the spacer grid type [6,7]. A series of four-subchannel CFD simulations to analyze the heat transfer enhancement in a fully heated rod bundle with vane spacers were performed by In et al [8]. By adjusting model coefficients adopted in a quadratic -model, Baglietto and Ninokatahad previously have shown the promising capability of the RSM turbulence model in sufficiently accurate anisotropy modeling of the wall shear stress distribution and the velocity field in tight lattice fuel bundles [9].…”