RETRAN-3D程序PWR DNB模型评价研究

Evaluation Study of the PWR DNB Model in the RETRAN-3D Code

分别选用RETRAN-3D程序中用于计算压水堆(PWR)偏离泡核沸腾(DNB)的四个临界热流密度关系式模型、以国际5 ×5压水堆燃料组件临界热流密度实验数据为输入热工参数,计算了高、中、低压力范围内共35个实验工况的最小偏离泡核沸腾比(MDNBR),并以子通道程序FLICAIII-F的计算结果为参考基准对RETRAN-3D程序的计算结果进行了评价研究,重点分析了W-3公式、B&W-2公式、MacBeth公式和Bowring公式在较宽压力范围内的计算准确性,结果表明:W-3公式在高、中、低压力范围内计算准确度较其余三个公式好,且在高、中压力范围内与子通道分析结果最为接近;B &W-2公式相对比较适合中、高压范围内的计算,但在高压下偏差稍大,而在低压下偏差更大;MacBeth公式适合低压范围内计算,在中、高压下偏差较大;Bowring公式适合在高、中压范围内计算,在低压下误差较大。综上分析可得出:在用RETRAN-3D程序计算压水堆在较宽压力瞬变范围内的堆芯MDNBR值时,优选公式为W-3公式。

The paper separately chooses four critical heat flux correlations in the RETRAN-3D code which is used for Pressurized Water Reactor (PWR) Departure Nucleate Boring (DNB) calculation. Based on the international 5 ×5 pressurized water reactor fuel assembly critical heat flux experimental data used for input thermal parameters, 35 total experimental cases with widely pressure range of high, middle, low pressure are calculated to obtain the Minimum DNBR (MDNBR) results. The results of RETRAN-3D code are compared with the basically exactly value from sub-channel code FLICAIII-F. The calculation accuracy of the W-3, B&W-2, MacBeth and Bowring formula in a wide range of pressure is specially analyzed. The results show that, the accuracy of the W-3 formula in a wide range of pressure is better than the other three formulas, and its results are most close to the sub-channel code results in the high and middle pressure range. It is acceptable for B&W-2 formula in the high and middle pressure range, but the deviation in the high pressure is big and especially bigger in low pressure. The MacBeth formula is proper for low pressure, not for high and middle pressure range. The Bowring formula can be used in high and middle pressure range, not in low pressure. The final conclusion is that, during the PWR core MDNBR calculation using RETRAN-3D code in the relatively wide pressure range, the preference critical heat flux model is W-3 formula.