| Abstract: | The Department of Energy Integrated Research Project (IRP) is developing a 50 MWe helium-cooled fast modular reactor (FMR), and has tasked Texas A&M University with conducting the thermal-hydraulic characterization of the baseline core configuration of the FMR. The experimental thermal-hydraulic investigation consisted of the axial and radial flow field characteristics in the hexagonal fuel rod bundle composed of 84 fuel rods, a central control rod, and spacer grids at a Reynolds number of 12,000. The experimental facility resembles one unit of the total fuel assembly and was constructed to be fully transparent to perform optical measurements. Time-Resolved Particle Image Velocimetry (TR-PIV) measurements were used to characterize hydraulic behavior downstream the spacer grid. In each orientation, using the PIV velocity vector fields, the full-field flow statistics were computed for the mean velocity, vorticity, and Reynolds stresses. An analysis of the energy decay downstream of the spacer grid was conducted with calculations of secondary-flow intensities, turbulent kinetic energy, power spectrum density, and spatial-temporal velocity cross correlations. Analysis in the two dimensional axial and radial flow statistics allowed for three dimensional conclusions and is shown in a 3D vorticity model. The data from this experimental campaign will be used to to validate numerical models based on Computational Fluid Dynamics (CFD) and other codes. The electronic version of this dissertation is accessible from https://hdl.handle.net/1969.1/197985 |
|---|