Development Considerations of AREVA NP Inc.'s Realistic LBLOCA Analysis Methodology

Table 4

Summary of uncertainty quantification exercise.

PIRT Parameter	Bias	𝜎	Min or −2𝜎	Max or +2𝜎
Break Size	N/A	N/A	0.1	2
Break discharge coefficients	###	###	###	###
Critical heat flux	###	0.0	###	###
Film boling HTC	###	Special	###	N/A
Dispersed film boiling	###	Special	###	N/A
Tmin,	###	###	###	###
Power (inc. radial and axial shapes)	Treated as a sampled plant parameter
Stored energy (centerline temperature)	###	###	###	###
Metal-water reaction constant	1	0.182	0.636	1.364
Metal-water reaction exponent	1	0.0134	0.9732	1.0268
Decay heat uncertainty	1	0.003	0.94	1.06
Condensation interface HTC	###	Uniform	###	###
Steam Generator Inlet Interphase Friction	###	0.0	###	###
Hot wall (CHF multiplier)	###	binary	###	###
Containment pressure (volume)	###	uniform	min free volume	max free volume