Nuclear Decay Heat Curves: U235 thermal
157680000 to 315360000
Decay heat power fraction vs time after shutdown for nuclear reactor design and spent fuel management. Covers U-235 thermal fission, U-238 fast fission, Pu-239 thermal fission, standard PWR (45 GWd/tHM), standard BWR (45 GWd/tHM), and MOX fuel per ANSI/ANS-5.1-2014. Time range: 1 second to 10 years. Includes dominant isotope contributors and 2-sigma uncertainty.
| fuel type | time after shutdown s | decay heat fraction of operating power (dimensionless) | standard | uncertainty pct 2sigma (%) |
|---|---|---|---|---|
| U235 thermal | 157,680,000 | 0.00036 | ANS 5.1 2014 | 5 |
| U235 thermal | 315,360,000 | 0.00021 | ANS 5.1 2014 | 6 |
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