Numerical study on modeling of liquid film flow under countercurrent flow limitation in volume of fluid method

作者：Watanabe Taro^*; Takata Takashi; Yamaguchi Akira

来源：Nuclear Engineering and Design, 2017, 313: 447-457.

DOI：10.1016/j.nucengdes.2016.12.038

• CCFL
• VOF method
• Liquid film flow
• Countercurrent annular flow
• Steam generator
• Numerical simulation

Countercurrent flow limitation (CCFL) in a heat transfer tube at a steam generator (SG) of pressurized water reactor (PWR) is one of the important issues on the core cooling under a loss of coolant accident (LOCA). In order to improve the prediction accuracy of the CCFL characteristics in numerical simulations using the volume of fluid (VOF) method with less computational cost, a thin liquid film flow in a countercurrent flow is modeled independently and is coupled with the VOF method. The CCFL characteristics is evaluated analytically in condition of a maximizing down-flow rate as a function of a void fraction or a liquid film thickness considering a critical thickness. Then, we have carried out numerical simulations of a countercurrent flow in a vertical tube so as to investigate the CCFL characteristics and compare them with the previous experimental results. As a result, it has been concluded that the effect of liquid film entrainment by upward gas flux will cause the difference in the experiments.

• 出版日期2017-3