Fig. 1. Diagram of fuel assembly pressure drop and natural circulation test facility (a) Pressure test section, (b) Natural circulation test section

Fig. 2. Flow of natural circulation flow rate solution

Fig. 3. Comparison of temperatures predicted by the model and experimental values under different heating powers(a) 1.5 kW, (b) 2.5 kW, (c) 3.0 kW

Fig. 4. Comparison of natural circulation flow rate measured by the experiment and predicted by the model under different heating powers

Fig. 5. Comparison of predicted natural circulation flow rate and experimental value

Fig. 6. Comparison of predicted axial temperature and experimental values

Fig. 7. Variations of natural circulation flow rate and peak cladding temperature with total heating power

Fig. 8. Variations of natural circulation flow rate and peak cladding temperature with ambient temperature

Fig. 9. Variation of natural circulation flow rate with relative humidity

Fig. 10. Variation of saturated vapor pressure of steam with temperature

Fig. 11. Variations of peak cladding temperature with relative humidity under different temperatures