Fuel element for a pressure water nuclear reactor, with a number of fuel rods, has spaced holders in grid cells with flow units to give structured cool water flows

摘要

The fuel element for a pressure water nuclear reactor has a number of fuel rods (2) within a number of spaced holders (4d) axially displaced from each other. It is composed of a number of grid cells (6) formed by grid bars (20), arranged in rows and columns. The grid bars have flow units (26) to develop flows of coolant water, with a lateral flow component parallel to the plane of spaced holders. At least one spaced holder has a number of part-sections (50a-50d), each larger than a grid cell, to divide the lateral cool water flow, and a cool water change is generally only in the lower flow channels (30) within the part-sections.