Analysis of Fission Products’ Release in Pebble-Bed High-Temperature Gas-Cooled Reactor Fuel Elements Using a Modified FRESCO II Numerical Model

Table 4

Comparison of two methods for Cs-138 fractional release rates from a pebble.

Temperature (°C)	600	700	800	900	1000	1100	1200	1300	1400	1500	1600
FRESCO-II (s^−1)	1.6609E − 15	2.1412E − 14	1.6480E − 13	7.8264E − 13	2.3831E − 12	5.3521E − 12	1.0020E − 11	1.6930E − 11	3.1376E − 11	8.9169E − 11	3.0714E − 10
FERRA (s^−1)	1.6609E − 15	2.1412E − 14	1.6480E − 13	7.8264E − 13	2.3831E − 12	5.3521E − 12	1.0027E − 11	1.7014E − 11	3.1707E − 11	8.9918E − 11	3.0952E − 10
Ratio	1.0000	1.0000	1.0000	1.0000	1.0000	1.0000	0.9993	0.9951	0.9896	0.9917	0.9923