Computational-Experimental Investigations of the Processes of Motion of a Coolant Flow in the Region of the Guide Channel Behind Mixing Grids of Fuel Assemblies

In the paper, the authors have presented local hydrodynamic characteristics (averaged-velocity vector fields) of the flow behind various types of intensifier grids of TVS-Kvadrat fuel assemblies intended for operation in pressurizedwater- reactor (PWR) cores. The structure of the flow behind these structural elements of the cassette has been revealed and the influence of the shape and orientation of turbulizers on the stabilization (equalization) length of transverse velocities in the characteristic regions of an assembly has been determined. The acquired information of the experimental investigations was used during the engineering substantiation of the TVS-Kvadrat structure for installing these assemblies into rector plants.