Environmental Engineering Reference
In-Depth Information
q
- neutron flux change
t
0
- time of sudden change
t
1
- time when neutron flux resume initial value
In order to demonstrate the determination of numerical value of the Resilience
Index due to sudden change of neutron flux it is assumed to have 10 % of the
average neutron flux and time interval for the neutron flux recovery Δt = 60
sec.. If we assume to have linear function of the neutron flux change in time
the Resilience Index will be
t
R
NF
2
NF
NF
(5)
With this numerical value of the parameters the Resilience index will be R =
30/0.1 = 300 /sec
3.6.2.2.2. Change of the Pressure in Primary Cycle
The pressure change in the primary cycle of nuclear reactor is usually
result of the reactor. power change. It is usually the result of the change in the
secondary cycle cooling.. Any reactor scram is leading to the sudden pressure
change in the primary reactor cycle.. The recovery of the sudden change in
reactor pressure is possible if the change is not large. In this respect only very
small change can be by the available resilience capacity of the system. The
primary cycle reactor pressure for the water cooled reactor around 160 bars.
The resilience capacity for the reactor pressure can be defined as the sudden
pressure change divided by the nominal reactor pressure.
Resilience Index due to sudden change of reactor pressure will be
tt
1
R
[100
q
]
dt
(6)
RP
RP
tt
0
where
q
- reactor pressure
RP
