Monitoring system for a liquid-cooled nuclear fission reactor
- Bolingbrook, IL
A monitoring system for detecting changes in the liquid levels in various regions of a water-cooled nuclear power reactor, viz., in the downcomer, in the core, in the inlet and outlet plenums, at the head, and elsewhere; and also for detecting changes in the density of the liquid in these regions. A plurality of gamma radiation detectors are used, arranged vertically along the outside of the reactor vessel, and collimator means for each detector limits the gamma-radiation it receives as emitting from only isolated regions of the vessel. Excess neutrons produced by the fission reaction will be captured by the water coolant, by the steel reactor walls, or by the fuel or control structures in the vessel. Neutron capture by steel generates gamma radiation having an energy level of the order of 5-12 MeV, whereas neutron capture by water provides an energy level of approximately 2.2 MeV, and neutron capture by the fission fuel or its cladding provides an energy level of 1 MeV or less. The intensity of neutron capture thus changes significantly at any water-metal interface. Comparative analysis of adjacent gamma detectors senses changes from the normal condition with liquid coolant present to advise of changes in the presence and/or density of the coolant at these specific regions. The gamma detectors can also sense fission-product gas accumulation at the reactor head to advise of a failure of fuel-pin cladding.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- DOE Contract Number:
- W-31109-ENG-38
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Number(s):
- US 4649015
- OSTI ID:
- 866171
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ex-core water-level monitor: comparison of computations with LOFT data
Aircraft Nuclear Propulsion Project Quarterly Progress Report for Period Ending February 20, 1950
Related Subjects
liquid-cooled
nuclear
fission
reactor
detecting
changes
liquid
levels
various
regions
water-cooled
power
viz
downcomer
core
inlet
outlet
plenums
head
density
plurality
gamma
radiation
detectors
arranged
vertically
outside
vessel
collimator
means
detector
limits
gamma-radiation
receives
emitting
isolated
excess
neutrons
produced
reaction
captured
water
coolant
steel
walls
fuel
control
structures
neutron
capture
generates
energy
level
5-12
mev
provides
approximately
cladding
intensity
significantly
water-metal
interface
comparative
analysis
adjacent
senses
normal
condition
advise
presence
specific
sense
fission-product
gas
accumulation
failure
fuel-pin
water-cooled nuclear
power reactor
neutrons produced
comparative analysis
fission reactor
liquid coolant
product gas
energy level
nuclear power
reactor vessel
neutron capture
liquid level
radiation detector
gamma radiation
radiation detectors
cooled nuclear
detecting changes
nuclear fission
reactor walls
outlet plenum
water coolant
reactor wall
reactor head
normal condition
gamma detector
metal interface
liquid levels
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