HTR-ESS的堆芯物理仿真方法研究

为满足高温气冷堆工程模拟仿真系统（HTR-ESS）中实时的要求，研究开发了三维圆柱几何堆芯多群中子时空动力学改进准静态方法模拟计算程序，使中子动力学程序满足模拟过程的实时要求。模型利用拟合公式计算宏观截面，使截面可实时反映堆芯状态，与堆芯热工形成反馈。针对高温气冷堆中控制棒的特点，提出使用等效吸收体的方法对控制棒进行等效，等效方法避免了在计算中出现控制棒移动与网格不匹配的问题。最后给出动态过程的简单模拟结果，显示了建立的堆芯物理实时计算模型满足设计条件和要求。

Study on Reactor Core Physics Simulation Method in HTR-ESS

The 3D temporal/spatial dynamics of multigroup neutron inside a cylindrical reactor core was simulated with an improved quasi-static method in the high-temperature gas-cooled reactor engineering simulation system (HTR-ESS). Macro cross section area in this model was fitted with polynomial equations. The state of reactor core was related with reactor thermal-hydraulics using the fitting equations. The control rods in the reactor were substituted with an equivalent absorber based on their characteristics in the high-temperature gas-cooled reactor. This substitution avoided the problem grid mismatch due to the movement of the control rods in the computation. The method could solve the kinetics equation in real time. A preliminary simulation by this method shows that the new real-time computation model for the reactor physics satisfies the design requirements.