随机介质蒙卡中子输运与燃耗计算方法研究

The dispersion fuel with coated fuel particles has been more and more applied in the new advanced nuclear power systems. Meanwhile, its structural stochastic-media property brings challenges for reactor physics analysis. Deterministic or traditional Monte Carlo (MC) codes generally have to introduce approximations to treat the stochastic media, such as correcting cross sections or using repeated structures. Research on the advanced MC methods for simulating the stochastic media has become a worldwide hot topic. Based on the reactor Monte Carlo code RMC, this project intends to study accurate and efficient MC neutron transport and burnup methods for the stochastic media. The project mainly comprises the following work: 1) Research on the MC high-fidelity geometric modeling, transport simulation and acceleration methods for stochastic media. 2) Research on the MC transport and burnup calculation methods for the dispersion fuel in element, assembly and core level, which mainly focus on the pebble-bed and prismatic HTGRs and some advanced LWRs. 3) Research on the MC methods for simulating the molten-core material or some other types of stochastic medias in engineering. 4) Research on the coupling of MC and deterministic methods. The project seeks to conducted a systematic study on the MC methodologies for the general stochastic media, and develop an advanced MC code system for the analyses of the dispersion fuel and some other form of stochastic medias. We believe this project has both significant academic meanings and great application values.

包覆颗粒弥散型燃料在新型先进核能系统中获得越来越多的应用，其结构上的随机介质属性给反应堆物理分析带来挑战。确定论或传统蒙卡程序通常只能近似模拟随机介质，譬如修正群截面、采用重复结构等。随机介质先进蒙卡计算方法研究已成为国内外研究热点。本课题拟基于自主堆用蒙卡程序，研究精确高效处理随机介质的蒙卡中子输运与燃耗计算方法。拟开展的工作主要包括: 1）研究随机介质蒙卡精确几何建模、输运模拟和加速方法；2）以球床式/棱柱式高温气冷堆和某些先进型水堆为主要对象，研究弥散型燃料元件、组件和堆芯层次的蒙卡输运和燃耗计算方法；3）研究堆芯熔融物等其它随机介质的蒙卡模拟方法；4）研究随机介质蒙卡和确定论耦合计算方法。课题致力于系统研究具有普适性的随机介质蒙卡计算理论与方法，自主开发可用于包覆颗粒弥散型燃料设计以及其它类型随机介质分析的先进蒙卡软件平台，具有十分重要的学术意义和明确的实际应用价值。

包覆颗粒弥散型燃料在高温气冷堆等先进核能系统中获得越来越多的应用，但其结构上的随机介质属性给反应堆物理分析带来挑战。随机介质先进蒙卡计算方法研究已成为国内外研究热点。项目基于自主研发的反应堆蒙卡程序RMC，研究精确高效处理随机介质的蒙卡中子输运与燃耗计算方法。.项目开展的研究内容包括：1）随机介质蒙卡精确几何建模、输运模拟和加速方法；2）高温气冷堆弥散型燃料元件、组件和堆芯的蒙卡输运和燃耗计算方法；3）压水堆FCM燃料计算方法，包括蒙卡显式模拟方法与改进反应性物理模型转换方法；4）基于等效均匀化的随机介质确定论计算方法。.项目取得的主要成果包括：1）建立了具有普适性的随机介质蒙卡输运与燃耗计算框架；2）基于蒙卡程序RMC开发了精确高效的随机介质模拟功能，使得RMC成为国际上少数几个可用于随机介质分析的蒙卡程序；3）自主研发了高温气冷堆物理设计软件包XPZ-PANGU，有望用于未来高温气冷堆设计与出口；4）培养了博士生3名，发表学术论文10余篇，申请软件著作权2项。.本项目不仅系统深入研究了随机介质蒙卡模拟方法，而且形成了可用于高温气冷堆包覆颗粒燃料、压水堆FCM燃料以及其它类型随机介质分析的先进自主软件平台，具有重要的学术意义和工程应用价值。