hee cheon no nuclear system/hydrogen lab. kaist
DESCRIPTION
Chapter 2: Reactor Heat Generation. Hee cheon NO Nuclear System/Hydrogen Lab. KAIST. Contents. 2.1 Energy release and deposition 2.2 Fission energy generation after reactor scram 2.3 Decay heat generation A2.1 Appendix. 2.1 Energy release and deposition. Fission chain reaction:. - PowerPoint PPT PresentationTRANSCRIPT
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Hee cheon NO
Nuclear System/Hydrogen Lab.
KAIST
Chapter 2: Reactor Heat Genera-tion
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Contents
2.1 Energy release and deposition
2.2 Fission energy generation after reactor scram
2.3 Decay heat generation
A2.1 Appendix
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2.1 Energy release and deposition
Forms of energy release
instanteneous re-lease
delayed re-lease
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2.1 Energy release and deposition
Fission energy release process
instanteneous re-lease
delayed re-lease
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2.1 Energy release and deposition
Instanteneous energy release from fission
Delayed energy release form fission
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Prompt fission energy release
Example
2.2 Fission energy generation after reactor scram
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2.2 Fission energy generation after reactor scram
Delayed neutron precursors
Delayed neutron six-group constants
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2.2 Fission energy generation after reactor scram
One-group approximation of six-group point kinetics equations
One group constants for U235:
/ [( ( ) ) / ]
/ [ / ]
dn dt t n C
dC dt n C
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2.2 Fission energy generation after reactor scram
Fission energy generation rate after reactor scram
=>
/ [( ( ) ) / ]
/ [ / ]
dn dt t n C
dC dt n C
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2.2 Fission energy generation after reactor scram
Solution of one-group approximation:
-0.05 reactivity withdrawl of solutions of one-group approximation with One group constants for U235:
, , ,0
, , ,0
( ) / [ / ( ) exp( ( ) / ) / ( ) exp( / ( ))]
[ / ( ) exp( ( ) / )] [ / ( ) exp( / ( ))]&int
( ) / ~ / ( ) exp( / ( ))] ~ 1/ (1 / );
Rx f Rx f
Rx f Rx f
Q t Q t t
For t t ial jump or drop
Q t Q t promp jump or drop
| ( ) | / | ( ) | ( : )t t Note
promp jump=0.13
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2.2 Fission energy generation after reactor scram
+0.0015 reactivity insertion of solutions of one-group approximation with One group constants for U235:
promp jump=1.25
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Total heat generation rate
Total heat generation rate=Heat generation rate by fission(prompt+delayed neutrons) and Decay heat geenration rate
HW#2: Chapt.2 #5+#6
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2.3 Decay heat generation
Empirical Decay heat cuve of ANS-5 for U235 (Patterson-Schlitz)
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2.3 Decay heat generation
Simple Decay heat cuve of ANS-5 for U235(1968)
Glasstone's ANS-5.1(1971)
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2.3 Decay heat generation Long-term (beyond 100yrs): decay heat cuve
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2.3 Decay heat generation Long-term (beyond 100yrs):
decay heat cuve
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2.3 Decay heat generation Long-term (beyond 100yrs): Radioactivity