Comprehensive parameter analyses on steam-air condensation at pressures up to 1.6 MPa.

• Experiments were conducted at pressures up to 1.6 MPa and subcooling up to 128 °C. • The air deterioration effect obviously weakens with the increase of pressure. • The power exponents of pressure and subcooling were clarified in wider ranges. • A more generalized experimental correlation was proposed based on 1500 data points. In loss of coolant accidents, steam condensation containing air is one of the most important thermal–hydraulic phenomena inside nuclear reactor containment. To evaluate the relation amongst heat transfer coefficients (HTCs) and thermal parameters, e.g., gas pressure, concentration and wall subcooling etc., several experimental correlations were fitted in previous studies. However, these experiments were performed at pressures lower than 0.6 MPa, thus the proposed correlations may not be suitable for integrated nuclear reactor containments with a design pressure greater than 1.0 MPa. To further evaluate this problem, the study carried out experiments at pressures from 0.15 to 1.6 MPa and wall subcooling from 20 to 128 °C. The effects of pressure and wall subcooling on tube external condensation HTCs were discussed. The results indicate that the non-condensable gas deterioration effect obviously weakens with the increase of pressure, and the power exponents of pressure, wall subcooling and mass fraction were clarified according to the broad-range experimental data. Based on the 1500 data collected from the present experiment and the Su, Fan, Dehbi experiments, a more generalized experimental correlation was proposed with deviations generally within ± 15%, which unified the data from different experiments in various parameter ranges. [ABSTRACT FROM AUTHOR]