三维离散纵标方法在反应堆精细屏蔽计算中的应用研究

随着计算能力的发展,三维离散纵标方法(SN)已逐渐为反应堆辐射屏蔽计算的主流方法之一。本文就三维SN方法应用于反应堆的精细化屏蔽建模与分析的关键问题进行了研究,主要包括精细化几何建模、堆芯固定源模型的创建和数据库截面参数敏感性分析等内容。在此基础上,本文以典型的压水反应堆为对象,构建了精细的三维SN计算分析模型,以压力容器快中子注量率为算例,完整实现了反应堆的精细化三维SN建模与分析,并将三维SN结果和蒙特卡罗方法的计算结果进行了比较分析。对比结果表明,精细化三维SN方法具有较高的计算精度,验证了三维SN方法在反应堆精细屏蔽计算问题中的有效性和正确性。

Study on the Application of Three-dimensional Discrete Ordinate Method in the high Precision Shielding Calculations of Nuclear Reactor

As the development of computing capacity,three-dimensional discrete ordinate (SN )method has become one of the main approaches of the nuclear reactor shielding calculation. This paper focuses on the key issues of the application of three-dimensional SN method in the reactor shielding calculation,including:the detailed geometry modeling approaches,the accurate specification of the core source,and the sensitivity analysis of the nuclear reaction cross sections. Moreover,a typical pressurized water reactor have been detailed modeled,the fast neutron flux on the inner surface of the reactor pressure vessel have been simulated. The results have been compared with the results of Monte Carlo methods,which show the high accuracy,effectiveness and correctness of three-dimensional SN method.