Numerical and experimental investigation of the water flow through PWR spacer grids

Spacer grids are one of main components a Pressurized Water Reactor (PWR) fuel assembly. They able to improve heat transfer from rod bundles the water flow by increasing turbulence and mixture this flow. On other hand pressure drop increases because spacer grids. Experimental Computational Fluid Dynamics (CFD) analysis have been used understand how affect This is important thermal-hydraulic performance. paper aims investigate numerically experimentally through PWR The numerical experimental procedures developed for 5x5 bundle with at Nuclear Technology Development Center (CDTN) in Belo Horizonte, Brazil. At CDTN, measurements velocity acquired 2D LDV (Laser Doppler Velocimetry) system results obtained using ANSYS CFX code. height downstream grid compared CFD simulations rate Reynolds number 5.4x104 . Results show good agreement between both methodologies. great repeatability low uncertainty evaluated (< 1.24%) work can be validate codes.