Fuel assembly with a grid structure between the rods
AssigneeSiemens Aktiengesellschaft
InventorsPeter Suchy, Gunter Bruch, Alexander Steinke, Franz-Josef Bokers
Life of this patent
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Abstract
In a fuel assembly, rods are disposed in meshes of a grid. Crossing points of the grid are distributed in a checker-board-like manner, partly in an upstream crossing plane and partly in a downstream crossing plane. Webs of the grid run in zigzag form between the two planes. As a result, flow resistance which is produced by the webs and/or by mixing vanes disposed thereon and by flow turbulences is shifted into different axial planes and is considerably reduced.
Claims18
A grid structure for an elongate fuel assembly, comprising:
- a) a grid having lateral surfaces defining meshes for guiding rods being parallel and next to one another, the rods defining interspaces therebetween forming flow channels for a stream of coolant flowing approximately parallel to the rods, the flow channels having center axes being spaced apart by a given distance between the center axes of neighboring flow channels, said lateral surfaces extending between the rods and having an end edge facing toward the stream of coolant and an end edge facing away from the stream of coolant;
- b) said end edges having upstream and downstream extreme points and a zigzag-shaped course between said extreme points with a half-period corresponding approximately to the given distance;
- and
- c) at least some of said downstream extreme points of said end edges facing toward the stream of coolant lying at least as far downstream as at least some of said upstream extreme points of said end edges facing away from the stream of coolant.
A grid structure for an elongate fuel assembly, comprising:
- a) a grid having webs defining meshes for guiding rods disposed parallel and next to one another for conducting a stream of coolant therebetween longitudinally through the fuel assembly;
- b) said webs extending in zigzag form between an upper crossing plane and a lower crossing plane, said webs having lateral surfaces extending between the rods and passing through one another at crossing points lying between the rods;
- c) the crossing points including a first group of crossing points lying in the upper crossing plane, a second group of crossing points lying in the lower crossing plane, and each two crossing points lying next to each other in said grid including one crossing point belonging to one of the groups and another crossing point belonging to the other of the groups.
A grid structure for an elongate fuel assembly, comprising:
- a) a grid having crossing points defining meshes therebetween for guiding rods disposed parallel and next to one another for conducting a stream of coolant therebetween longitudinally through the fuel assembly;
- b) mixing vanes protruding laterally into the stream of coolant at the crossing points lying between the rods;
- and
- c) the crossing points including first and second groups of crossing points, the crossing points of the first group each having at least one of said mixing vanes in a downstream crossing plane, and the crossing points of the second group each having at least one of said mixing vanes in an upstream crossing plane.
Dependencies are inferred from the claim text.