Lower tube base and light water reactor fuel assembly

Abstract

A lower tube base (100) and a light water reactor fuel assembly, the lower tube base (100) includes a coaming plate (10), a connecting column (20), a transverse thin strip (30) and a longitudinal thin strip (40), the surrounding The board (10) has a hollow structure through which the bottom has downward protruding legs (11). The hollow structure forms a cavity. In the cavity, both the horizontal thin strips (30) and the longitudinal thin strips (40) are fixedly connected to the enclosure (10), and the horizontal projections of the horizontal thin strips (30) and the longitudinal thin strips (40) intersect to form a staggered grid shape, the connecting column (20) runs through the horizontal thin strip (30) and the vertical thin strip (40) and is fixed with the penetrated horizontal thin strip (30) and the vertical thin strip (40); because the horizontal thin strip (30) and the vertical thin strip (40) The projections of the longitudinal thin strips (40) on the horizontal plane intersect to form a staggered grid, so that the entire lower tube base (100) forms a three-dimensional grid-like water flow channel, thereby improving the filtering capacity and reducing the pressure drop of water flow.

Description

technical field [0001] The invention relates to a light water reactor component, in particular to a light water reactor fuel assembly and its lower pipe seat. Background technique [0002] A certain number of fuel rods are arranged at certain intervals (such as: 15×15 or 17×17, etc.) and fixed into a bundle, which is called a reactor fuel assembly. Composed of tubes and fuel rods. Generally, reactor fuel assemblies are used in nuclear reactors for 3-5 years. Because they are in a strong neutron field, they need to withstand high temperature, high pressure, and high flow rate coolants, and at the same time they need to withstand the chemical action of fission products and complex mechanical loads. Therefore, the working conditions are very harsh. [0003] As we all know, the main purpose of setting up multi-layer protection for nuclear reactors is to ensure that after accidents such as nuclear reactor explosions, the radioactive substances in the nuclear reactor will not le...

AI Technical Summary

Problems solved by technology

[0004] The plate surface of the existing lower pipe seat usually has several water flow holes and connection holes on a whole plate according to the actual situation. In order to ensure that the plate surface has sufficient strength, a certain distance must be kept between the holes, so that The plate surface part also has a solid part with a larger area, so that when the water flow passes through the lower pipe seat, due to the obstruction of the solid part of the panel, the flow velocity of the water flow decreases after passing through the lower pipe seat, so the lower pipe seat has a greater pressure on the water flow drop, which may lead to a dangerous situation in the nuclear reactor; Note, the direction of water flow is from bottom to top, that is, from the lower end of the lower pipe seat to the upper end.

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