Development of critical heat flux correlation for In-vessel retention

Figures & data

Table 1. Range of plant conditions.

Parameter	Range
Pressure (MPa)	Atmospheric pressure–0.6
Thermal output (MWt)	1460–4510
Decay heat	0.6–1.2% of thermal output
Water level of reactor cavity (m)	1.8–8.3
Depth of cooling channel (mm)	150

Figure 1. Schematic drawing of natural circulation under IVR conditions.

Table 2. Estimation results of thermal hydraulic parameters corresponding to position in the reactor vessel.

	Inclination angle (°)
Parameters	15	50	70	90
Mass flux (kg/m^2s) Quality (-)	1400–5500 -2.9 × 10^−2 to -2.1 × 10^−3	480–1900 -2.6 × 10^−2 to -4.8 × 10^−4	420–1700 -2.5 × 10^−2 to 8.9 × 10^−4	360–1400 -2.0 × 10^−2 to 3.1 × 10^−3

Figure 2. Angular variation of heat flux for a two-layer composition (typical case in a large-scale PWR).

Figure 3. Angular variation of heat flux for a three-layer composition (typical case in a large-scale PWR).

Figure 4. Concept of the test section.

Figure 5. Schematic drawing of the test section.

Figure 6. Photo of the test section.

Figure 7. Loop diagram of the test equipment.

Figure 8. Time variation of heat flux and temperature in heater block.

Figure 9. Comparison between measured CHF data and ULPU data.

Table 3. Results of repeatability tests.

	First	Second	Third	Standard deviation
CHF (kW/m^2)	1962	1943	1982	19.5

Figure 10. Relationships between CHF and inclination angle.

Figure 11. Relationships between CHF and pressure.

Figure 12. Relationships between CHF and mass flux.

Figure 13. Relationships between CHF and thermodynamic quality.

Figure 14. Comparison of CHF between experiment and SULTAN correlation.

Figure 15. Comparison of CHF between experiment and developed correlation.