球床式水冷堆堆芯热工水力特性分析

Study on Thermohydraulic Characteristics of Pebble Bed Water Cooled Reactor Core

摘要: 以计算流体力学（CFD）为基础，对球床式水冷堆堆芯燃料元件进行三维建模、网格划分和数值计算，采用Fortran 90编制了用于球床式水冷堆堆芯热工水力计算和安全分析微机型仿真程序STAP和TSAP，并对球床式水冷堆堆芯稳态、瞬态工况进行热工水力计算。计算结果表明：燃料元件温度的最大值出现在微小间隙区域位置，速度最大值出现在与该元件接触的燃料元件微小间隙区域的中间位置；燃料元件的表面温度远小于该堆型的设计极限温度，满足安全准则；引入反应性扰动的瞬态工况下，冷却剂的温度突然增加，随后逐步下降，达到稳定。燃料元件表面温度逐步增加，然后逐步降低至稳定状态。

Abstract: Study on the thermohydraulic characteristics of the pebble bed water cooled reactor (PBWR). The physical and geometrical model of the PBWR were built in which the thermal-hydraulic characteristics of the coolant were studied based on the computational fluid dynamics (CFD), meanwhile, STAP and TSAP code were established using Fortran 90. The results show that the surface temperature of the fuel element is much less than the design limit of 1 600 ℃, the maximum temperature on the surface of fuel element appears near the narrow gap area and the maximum velocity of the fuel element appears in the neutral position of the four narrow gap regions.