Predictive and Experimental Study of Cross-Section Average Void Fraction in Sub-cooled Boiling with Natural Circulation

Sub-cooled average void fraction in natural circulation is investigated using high-temperature high-pressure RBI optical probe in this paper. The experimental data are compared with the existing Saha model, Levy model and Sun mass true quality model. The result shows that these models based on forced circulation do not fit in the natural circulation. The analyses of the experimental data in this paper indicate that the void fraction in natural circulation is higher than that in forced circulation. In addition, the Sun mass true quality model is improved in this paper, and the improved model agrees quit well with the experimental data in natural circulation .