典型压水堆堆芯物理-热工耦合稳态计算软件的开发与验证

Development and Verification of Typical PWR Core Physical and Thermal-hydraulic Steady Coupling Code

为能更加准确地模拟典型压水堆中强烈的物理-热工耦合现象,研制了压水堆堆芯物理-热工耦合计算软件ARMcc。其中物理计算模块基于四阶节块展开法(NEM)和格林函数节块法(NGFM),热工计算模块基于一维的单相单通道换热模型和一维圆柱导热计算模型,在程序中采用有限体积法和有限差分法求解一维圆柱导热模型。基于典型压水堆基准题NEACRP-L-335对程序的稳态耦合计算能力进行了验证,程序计算的堆芯关键参数如临界硼浓度、堆芯多普勒温度等参数与参考结果符合良好,临界硼浓度与参考结果的相对偏差均小于0.5%。另外研究4种计算模式对模拟堆芯物理-热工耦合过程的影响,选择PARCS程序计算结果为对比,发现NGFM+DIF模式能更加准确地模拟堆芯燃料多普勒温度和堆芯功率分布;NGFM+VOL模式能更加准确地模拟临界硼浓度;NEM+VOL模式能更加准确地模拟堆芯燃料最高温度。

In order to more accurately simulate the strong neutronics physical and thermal-hydraulic coupling phenomenon in a typical PWR,ARMcc,a software for the physical and thermal-hydraulic coupling calculation of PWR core,was developed.In the ARMcc program,the physical calculation module is based on the fourth-order nodal expansion method(NEM)and Nodal Green’s function method(NGFM),the thermal-hydraulic calculation module is based on one-dimensional single-phase single-channel heat transfer model and one-dimensional cylinder heat conduction calculation model.The finite volume method and finite difference method were used to solve heat conduction model in ARMcc program.Based on the typical PWR benchmark NEACRP-L-335,the ability of steady-state coupling calculation of the program was verified.The key parameters of the program,such as critical boron concentration and core Doppler temperature,are in good agreement with reference results.The relative deviation between the critical boron concentration and the reference results is less than 0.5%.In addition,the influences of the finite volume method and the finite difference method on the results of the coupling program were studied.The PARCS program was selected as the comparison program.It is found that NGFM+DIF mode can more accurately simulate the core fuel Doppler temperature and core power distribution,NGFM+VOL mode can more accurately simulate the critical boron concentration,and NEM+VOL mode can more accurately simulate the core fuel maximum temperature.