Arrangement optimization and threshold selection method of nuclear critical accident alarm system

Abstract

The invention relates to an arrangement optimization and threshold selection method of a nuclear critical accident alarm system. According to the method, a three-dimensional dose field analysis meansis adopted, attenuation of a dose field along with distance and shielding of adjacent equipment are accurately considered, and three-dimensional dose field distribution generated by a minimum criticalaccident source item and a normal operation source item is comprehensively analyzed; an appropriate nuclear critical accident alarm system arrangement point position is optimally selected from a plurality of dose field distribution maps and an alarm threshold value is reasonably selected by adopting a method of a minimum critical accident dose field distribution minimum contour map of each pieceof equipment so as to ensure that each piece of equipment with critical accident risks can be covered by the alarm threshold value, and model selection can be further carried out on the probe. The arrangement optimization and threshold selection method of the nuclear critical accident alarm system realizes comprehensive consideration of factors such as geometric arrangement, accident points and normal operation dosage in arrangement optimization and threshold selection of the nuclear critical accident alarm system, and is an advanced arrangement optimization and threshold selection method of the nuclear critical accident alarm system with engineering feasibility.

Description

technical field [0001] The invention relates to a nuclear criticality safety analysis technology for fissionable materials outside a reactor, in particular to a method for optimizing the layout of a nuclear criticality accident alarm system and selecting a threshold. Background technique [0002] The nuclear criticality accident alarm system is used to timely detect nuclear criticality accidents and trigger alarms to urge personnel to evacuate to prevent radiation exposure after the first peak of nuclear criticality accidents; Measure and mitigate to minimize the consequences of nuclear criticality accidents. Since the radiation exposure after the first peak is still large, the rapid evacuation response triggered by the nuclear criticality accident alarm system plays an important role in reducing the radiation dose of the operators. [0003] In the design of spent fuel reprocessing plants in my country, nuclear criticality accidents have been taken as design basis accidents...

AI Technical Summary

Problems solved by technology

[0005] In the design of the post-processing intermediate pilot plants that have been built in my country, due to the limitation of calculation means and the lack of design experience, the simplified treatment of single equipment and one-dimensional calculation is adopted, and the influence of other equipment and structural materials on neutrons or neutrons produced by critical accidents is not considered. The shielding effect of photons may cause the alarm threshold set by the critical accident alarm system to be too high, and the minimum critical accident in some parts may not be detected

Since there is no analysis of the three-dimensional dose field, the layout position of the critical accident alarm system cannot be optimized and analyzed, nor can it be carefully compared with the dose field during normal operation of the plant. Most of the critical accident alarm systems arranged in the post-processing intermediate test plant are conservative. more expensive neutron probes were chosen

In addition, part of the critical accident alarm system is arranged in an unreasonable position, such as inside the heat chamber, etc., which is inconvenient for maintenance and calibration in practical applications

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