自主化堆芯三维核设计软件COCO研发

中国广东核电集团正在开发的三维堆芯核设计软件COCO将具备堆内功率分布计算、精细功率分布计算、临界硼浓度搜索、控制棒临界搜索、核子密度计算等基本功能。COCO采用格林函数节块方法作为求解器计算堆芯的功率分布，采用单通道模型和棒传热模型来计算慢化剂的密度和燃料温度。COCO已实现从寿期初到寿期末的燃耗计算能力。通过与参考程序的数值比较发现，COCO采用的理论模型和耦合流程正确，计算精度可满足工程设计的需要。

Development of Self-Reliant Three-Dimensional Core Nuclear Design Code COCO

Three-dimensional (3D) core nuclear design code COCO is developed in China Guangdong Nuclear Power Holding Corporation (CGNPC), and the basic functions of COCO include core power distribution calculation, fine core power reconstruction, critical boron density search, critical control rod position search, and nuclear density calculation, etc. The COCO employed Green’s function nodal method as the key solver to calculate the core power distribution, and the single-channel model and the rod heat transfer model were used to calculate the moderator density and fuel temperature. The calculation capacity from the beginning of cycle to the end of cycle was achieved in the COCO code. Comparing  with the reference code’s values, the theoretical models and coupling processes used in the COCO is proved to be correct with sufficient calculating accuracy which can meet requirements for engineering design.