Visual fuel rod

Abstract

The invention provides a visual fuel rod. The visual fuel rod is characterized in that the visual fuel rod includes a lower plug (1), a fuel shell (2), a liquid column (3), an upper plug (4) and a positioning winding wire (5). The liquid column (3) is arranged in the fuel shell (2). The refractive index deviation of the liquid column (3) and the fuel shell (2) is within a range of 1%. The lower plug (1) and the upper plug (4) are connected to the two ends of the fuel shell (2) so as to seal the liquid column (3) in the fuel shell (2). The positioning winding wire (5) wraps and is fixed to theouter surface of the fuel shell (2). Through the arrangement of liquid with the same or similar refractive index with the fuel shell (2) in the fuel shell (2), the requirements of optical velocity measuring equipment for refractive index matching and transmittance can be satisfied, and the requirements of mechanical strength can be satisfied. The visual fuel rod can be used for studying a velocityfield, a pressure field and the like inside a fuel assembly.

Description

technical field [0001] The invention relates to the field of nuclear reactors, in particular to a visual fuel rod. Background technique [0002] Fuel assembly is a heat source with compact structure and high heat release rate per unit volume, and it is exposed to strong radiation for a long time. A typical liquid metal-cooled fast reactor fuel rod is a fuel rod bundle whose radial positioning is maintained by a spiral positioning wire or a grid-shaped positioning frame, and the axial positioning is maintained by a grid plate. The fuel rods are arranged in an equilateral triangle grid. The fuel assembly with positioning wires has a complex structure, dense flow channels, and lateral mixing, which can enhance heat transfer and reduce the probability of blockage. [0003] Liquid metal coolant is opaque, and non-contact optical velocity measurement technology cannot be used to observe the flow field inside the component. At the same time, liquid metal-cooled fast reactors oper...

AI Technical Summary

Problems solved by technology

[0004] If the selected fuel rods and working medium have poor light transmittance, it will be difficult or even impossible for the laser sheet light source to penetrate the fuel rods, which will make it difficult to obtain a clear velocity vector diagram during the experiment

If the refractive index deviation of the selected fuel rods and working fluid is large, it will cause serious refraction phenomenon after the laser light source enters the component, which will cause the distortion of the collected velocity vector image and cause a large measurement velocity error

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