对NOTRUMP-AP600程序缺少动量通量项的评估与修正

由于NOTRUMP-AP600程序的动量守恒方程缺少动量通量项，在分析用于模拟AP600核电厂的APEX试验台架小破口事故时，安全壳内置换料水箱注射流量和稳压器混合水位等参数的预测值和实验值有较大偏离。本文对此进行评估：1) 采用均相流和分相流模型计算动量通量项对AP600核电厂自动卸压系统（ADS）管路压降的影响；2) 采用FLOAD4程序对需修正的第4级ADS(ADS4)管路的两相流压降进行计算，预测ADS4管路内的压力分布，并用作修正NOTRUMP-AP600程序ADS4管路压降的基准。结果表明，对于AP600核电厂ADS4管路，输入阻力系数需增加60%。

Evaluation and Modification of NOTRUMP-AP600 Code With Neglecting Momentum Flux Terms

The momentum flux terms are not included in the momentum equations for NOTRUMP-AP600 code. The predicted injection mass flow rate of IRWST and pressurizer level deviate test results largely when NOTRUMP-AP600 code is used to analyze SBLOCA for APEX-600 test facility. The impact of neglecting the momentum flux terms in the NOTRUMP-AP600 was evaluated, including the following contents: The impact of neglecting momentum flux terms for the pressure drop of ADS line was calculated using homogenous model and separated flow model; the detailed two-phase pressure drop was calculated using FLOAD4 code for the ADS4 line, and the result was used to benchmark the ADS4 pressure drop for NOTRUMP-AP600. The results show that the input resistance coefficient should be increased by 60% for AP600 ADS4 line.