Fuel assembly structure and reactor core structure for enhancing temperature negative feedback of air-cooled fast reactor

Abstract

The invention relates to a fuel assembly structure and a reactor core structure for enhancing temperature negative feedback of an air-cooled fast reactor, wherein the fuel assembly is radially dividedinto three areas of an active area, a slowing-down area and an assembly box from inside to outside, the reactor core is radially arranged and divided into an inner fuel area and an outer fuel area according to different arrangement assemblies, coolant flow channels and special radial reflection layers are specifically arranged outside the fuel areas, the fuel area is axially provided with a lowerreflecting layer, a fuel layer, an air cavity and an upper reflecting layer from bottom to top, the fuel layer of the inner fuel area is axially subdivided into three layers, fuel is arranged at thetwo ends, a section of depleted uranium is arranged in the middle, coolant circulation uses double-flow-path design, and a coolant at an inlet inflows downwards from the fuel area and then outflows upwards from a specially-arranged out-of-reactor coolant flow channel. According to the invention, the structures can effectively enhance the temperature negative feedback of air-cooled fast reactors and improve the inherent safety of air-cooled reactors.

Description

technical field [0001] The invention belongs to the technical field of nuclear reactor engineering, and in particular relates to a structure for enhancing the temperature negative feedback of an air-cooled fast reactor. Background technique [0002] Common coolants for gas-cooled fast reactors include helium, helium-xenon mixed gas, and the like. Compared with the current pebble bed high-temperature gas-cooled reactor, the gas-cooled fast reactor can achieve higher power density and effectively reduce the volume of the core. At the same time, the gas working fluid cooling cycle adopts the Brayton cycle, which has higher cycle efficiency; there is no phase change in the whole process, and the steam generator, pressurizer, steam-water separator and dryer used in the pressurized water reactor are not needed. Compact, greatly reducing the volume and weight of the thermal system. [0003] Based on the advantages of gas-cooled fast reactors, it is expected to be applied to the d...

AI Technical Summary

Problems solved by technology

However, the moderation ability of the gas coolant to neutrons is weak, the core energy spectrum is relatively hard, and the fuel Doppler negative feedback effect of the reactor is not strong. The feedback effect caused by gas expansion is weak at high temperature; the overall temperature negative feedback of the core is much weaker than that of other reactor types, which brings significant safety challenges

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