Numerical analyses of flow structure and heat transfer flow structure and heat transfer flow structure and heat transfer flow structure and heat transfer downstream of mixing vane of spacer grid in fuel assembly

The present work analyzed the effect of mixing vane shape on the flow structure and heat transfer downstream of mixing vane in a subchannel of fuel assembly, by obtaining velocity and pressure fields, flow-mixing factors, heat transfer coefficient and friction factor using three-dimensional RANS analysis. Split vane as a typical mixing vane and SG1 and SG2, which are designed by the authors, were tested to evaluate the performances in enhancing the heat transfer. Standard k-ε model is used as a turbulence closure model, and, periodic and symmetry conditions are set as boundary conditions. It reveals that heat transfer rate is affected significantly by swirl and cross-flow as well as by the flow blockage