Pebble-bed high-temperature gas cooled reactor high neutron multiplication performance fuel element

Abstract

The invention provides a pebble-bed high-temperature gas cooled reactor high neutron multiplication performance fuel element. The element comprises a graphite cladding and a graphite matrix from outside to inside, wherein a plurality of coated fuel particles are uniformly distributed in the graphite matrix according to spherical coordinates, each coated fuel particle comprises a uranium dioxide core particle and a coating layer from inside to outside in the radial direction, each coating layer sequentially comprises a loose pyrolytic carbon layer, an inner compact pyrolytic carbon layer, a silicon carbide layer and an outer compact pyrolytic carbon layer from inside to outside, and the thickness of each layer of the coating layer is obtained by multi-objective optimization under the condition that the diameter and the enrichment degree of the uranium dioxide core particles are fixed. According to the invention, the neutron multiplication performance is improved from the perspective ofoptimizing the thickness of each layer of the coating layer, the purpose of improving the neutron performance by simply increasing the diameter or the enrichment degree of the core particles in the past is avoided, and experiments prove that the neutron performance is improved, and the pebble-bed high-temperature gas cooled reactor high neutron multiplication performance fuel element has very strong economic advantages.

Description

Technical field [0001] The invention belongs to the technical field of nuclear reactors, and in particular relates to a fuel element with high neutron multiplication performance for a pebble bed type high temperature gas-cooled reactor. Background technique [0002] In recent years, with my country’s rapid economic growth and environmental protection requirements, the demand for nuclear energy has increased dramatically. Compared with other reactors, the high-temperature gas-cooled reactor has the advantages of high power generation efficiency, good safety performance, and small-capacity modular construction. It can be used in applications such as nuclear hydrogen production and high-efficiency power generation. It is a new generation of advanced reactors that are vigorously developed in the world. one. The United Kingdom, the United States, and Germany started the research and development of high-temperature gas-cooled reactors in the early 1960s, and successively built three e...

AI Technical Summary

Problems solved by technology

In the prior art, as far as the reactor is concerned, the neutron multiplication performance is generally improved by increasing the fuel charge, that is, increasing the core diameter of uranium oxide (thorium) or uranium carbide (thorium) or increasing the fuel enrichment degree However, the fuel core material is expensive, and it is urgent to consider how to improve the neutron multiplication performance and economic efficiency under the condition of a fixed fuel charge from other perspectives.

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