Input Calibration and Validation of RELAP5 Against CIRCUS-IV Single Channel Tests on Natural Circulation Two-Phase Flow Instability

Table 7

Calculated and experimental values with uncertainties.

Parameters			I-1						I-2
			Exp.	Calib. input	Uncertainty				Exp.	Calib. input	Uncertainty
					Exp.; Unc.	Calc.; Unc.; (+)	Calc.; Unc.; (−)				Exp.; Unc.	Calc.; Unc.; (+)	Calc.; Unc.; (−)
Oscillation period (s)			49.1	62.4	±0.1	11.6	15.2		14.3	14.2	±0.1	0.4	2.4
Flow rate (L/s)	Average		0.058	0.062	±0.01	0.002	0.005		0.126	0.126	±0.07	0.007	0.006
	Maximum		0.235	0.225	−0.015	0.078	0.085		0.282	0.329	−0.007	0.050	0.000
	Minimum		0.024	0.031	+0.017	0.004	0.001		0.029	0.036	+0.009	0.000	0.009
Inlet riser temp. (°C)	Average		105.6	104.4	±0.1	0.5	0.2		106.0	105.6	0.0	0.308	0.246
	Maximum		109.0	108.0	−0.4	0.1	0.1		110.2	108.9	−1.0	0.089	0.209
	Minimum		98.1	97.7	−0.1	1.3	0.6		103.9	103.3	+0.1	0.515	0.401
Middle riser temp. (°C)	Average		102.2	102.0	±0.1	0.5	0.3		104.3	104.2	0.0	0.023	0.617
	Maximum		106.4	106.4	−0.1	0.3	0.3		107.3	106.0	−0.3	0.453	0.096
	Minimum		98.8	98.4	+0.1	0.7	0.6		102.9	103.4	+0.1	0.165	0.911
Outlet riser temp. (°C)	Average		102.0	100.8	0.0	0.7	0.4		103.8	102.6	−0.2	0.054	1.454
	Maximum		104.5	104.8	−0.3	0.0	0.1		105.2	103.8	−0.3	0.421	0.094
	Minimum		99.9	98.6	−0.1	0.7	0.6		102.7	101.1	+0.2	0.000	1.704
Inlet pressure (bar)	Average		1.651	1.653	0.000	0.002	0.001		1.642	1.648	0.000	0.003	0.011
	Maximum		1.653	1.657	±0.013	0.004	0.000		1.660	1.665	±0.020	0.012	0.007
	Minimum		1.595	1.624	±0.002	0.020	0.028		1.584	1.596	±0.004	0.009	0.023