Control rod guide tube and fuel assembly

Abstract

The invention discloses a control rod guide tube, which is inserted in a spacer grid, the control rod guide tube has a hollow tubular structure, and several flow-disturbing openings through the sidewall of the control rod guide tube are provided with the control rod guide tube. According to the flow-disturbing openings on the sidewall of the control rod guide tube, fully mixing of cryogenic fluid on a cold wall surface and hot fluid on a hot wall surface in a cold wall lattice cell occupied by the control rod guide tube can be realized, fluid on the cold wall surface in the cold wall lattice cell can participate in channel heat exchange, thereby CHF performance of the control rod guide tube can be enhanced. The flow-disturbing opening can adjust the fluid resistance when the control rod drops, further the rod-dropping performance of the control rod under accident can be improved. Correspondingly, the invention also provides a fuel assembly possessing the control rod guide tube.

Description

technical field [0001] The invention relates to a reactor component, in particular to a fuel assembly control rod guide tube capable of enhancing critical heat flux density and rod drop performance. 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. Generally, it consists of an upper positioning grid, a lower positioning grid and 6-8 intermediate positioning grids), control rod guide tubes and fuel rods. Among them, the control rod guide tube is the load-bearing part of the fuel assembly framework, and its main functional requirements are: (1) connecting the upper and lower pipe sockets to form the component framework and providing continuity for the component structure; (2) providing insertion for the related component rods; (3) provide a buffering effect for rapid rod drop shutdown in an accident, and prevent excessive impact force b...

AI Technical Summary

Problems solved by technology

The control rods in the control rod guide tube will not generate heat because they do not participate in the chain reaction. The channel containing this control rod guide tube is a typical cold wall channel (also known as the cold wall cell), and the cold wall cell in the cold wall cell The cold fluid on the wall surface (that is, the outer wall of the control rod guide tube) will only flow from upstream to downstream along the cold wall surface, without fluid mixing with the hot fluid on the hot wall surface, so usually the control rod guide tube channel will become The short board of CHF performance of fuel assemblies limits the overall CHF performance of fuel assemblies

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