一种有效缓解中子反照效应的堆坑小室通道屏蔽墙设计

The Design of the Shielding Wall of Reactor Pit Chamber Adit that Can Effectively Mitigate the Neutron Albedo Effect

本研究以中子与物质相互作用的基本原理为基础,通过推演的方式进一步探究了悬挑结构抑制反照中子产额的机理,并基于此机理,创造性地提出了一种新型屏蔽墙。该新型屏蔽墙在不改变原有墙体厚度和材料种类的前提下实现了抑制反照中子产额的功能。为验证该新型屏蔽墙对反照中子总数的影响,以百万千瓦级压水堆核电机组功率运行期间反应堆厂房内的中子能谱作为输入条件,采用蒙特卡罗模拟结合加权计算的方式进行研究,发现与平面屏蔽墙相比该新型屏蔽墙能够减少系统中约46.56%的反照中子产额。

This article further explores the mechanism of restraining albedo neutrons by the cantilever structure through deduction based on the basic principle of neutrons’interaction with matters,and a new type of well¬shaped shielding wall is proposed by summarizing the mechanism.This new type of shielding wall realized the purpose of restraining albedo neutrons without changing the material and thickness of the original wall.In order to verify the influence of the well-shaped shielding wall on the total number of albedo neutrons,the neutron energy spectrum in the reactor building during power operation of a 1000 MWe pressurized water reactor measured in reference[4]is taken as the input condition,and the Monte-Carlo simulation combined with weighted calculation is used in this study.It found that the application of the well-shaped shielding wall is able to reduce the albedo neutrons by 46.56%compared with the normal shielding wall.