| 摘要 |
<p>The lower tie plate grid (16) includes cylindrical bosses (32) and webs (38) interconnecting the bosses for supporting nuclear fuel rods and defining flow channels (40) through the grid for flowing coolant upwardly about the fuel rods. The grid includes shaped body members (42) having flow openings (52), the members being disposed in each of the flow channels. In one form, the members define with the side walls of the bosses and webs a debris retention zone (50). In another form, sets of generally parallel, laterally spaced bars (80,82) are disposed at discrete elevations in the flow channels. The bars are orthogonally related to one another whereby the effective debris catching area is defined by the openings through the crossed bars in plan, while the coolant flow area comprises essentially the space between each set of bars. <IMAGE> <IMAGE> <IMAGE></p> |
