An autonomous system of a spent fuel pool cooling in WWER-1000
The issue of WWER-1000 spent fuel pool cooling in total blackout conditions is evaluated. A model of a spent fuel pool for MELCOR computer code is developed. Basic information about a spent fuel pool construction is shown. Basic data for a spent fuel pool cooling system calculations are given. A sch...
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nasplib_isofts_kiev_ua-123456789-1360342025-02-09T13:36:25Z An autonomous system of a spent fuel pool cooling in WWER-1000 Автономна система охолодження басейну витримки відпрацьованого ядерного палива на АЕС з реактором ВВЕР-1000 Автономная система охлаждения бассейна выдержки отработанного ядерного топлива на АЭС с реактором ВВЭР-1000 Ihschenko, O.P. Проблемы современной ядерной энергетики The issue of WWER-1000 spent fuel pool cooling in total blackout conditions is evaluated. A model of a spent fuel pool for MELCOR computer code is developed. Basic information about a spent fuel pool construction is shown. Basic data for a spent fuel pool cooling system calculations are given. A scheme of a spent fuel pool autonomous cooling system as well as calculation results of its operation are provided. The analysis results of of the autonomous cooling system operation is performed. The calculation of the autonomous cooling system equipment is done. Necessary network parameters are defined. The approximate cost of the cooling system is determined. Розглянуто проблему охолодження води в басейні витримки при знеструмленні. Побудовано нодалізаційну схему басейну витримки, що розроблена за допомогою розрахункового коду MELCOR. Наведено вихідні дані розрахунків системи охолодження і продемонстровано схему автономної системи охолодження басейну витримки. Наведено результати моделювання функціонування даної системи. Проведено аналіз отриманих результатів моделювання. Виконано розрахунок обладнання системи охолодження води басейну витримки, визначені необхідні параметри мережі і орієнтовна вартість системи охолодження. Рассмотрена проблема охлаждения воды в бассейне выдержки при обесточивании. Построена нодализационная схема бассейна выдержки, разработанная с помощью расчетного кода MELCOR. Приведены исходные данные расчетов системы охлаждения и продемонстрирована схема автономной системы охлаждения бассейна выдержки. Приведены результаты моделирования функционирования данной системы. Проведен анализ полученных результатов моделирования. Выполнен расчет оборудования системы охлаждения воды бассейна выдержки, определены необходимые параметры сети и ориентировочная стоимость системы охлаждения. 2017 Article An autonomous system of a spent fuel pool cooling in WWER-1000 / O.P. Ihschenko // Вопросы атомной науки и техники. — 2017. — № 2. — С. 117-123. — Бібліогр.: 8 назв. — англ. 1562-6016 https://nasplib.isofts.kiev.ua/handle/123456789/136034 621.039.586 en Вопросы атомной науки и техники application/pdf Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Проблемы современной ядерной энергетики Проблемы современной ядерной энергетики |
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Проблемы современной ядерной энергетики Проблемы современной ядерной энергетики Ihschenko, O.P. An autonomous system of a spent fuel pool cooling in WWER-1000 Вопросы атомной науки и техники |
| description |
The issue of WWER-1000 spent fuel pool cooling in total blackout conditions is evaluated. A model of a spent fuel pool for MELCOR computer code is developed. Basic information about a spent fuel pool construction is shown. Basic data for a spent fuel pool cooling system calculations are given. A scheme of a spent fuel pool autonomous cooling system as well as calculation results of its operation are provided. The analysis results of of the autonomous cooling system operation is performed. The calculation of the autonomous cooling system equipment is done. Necessary network parameters are defined. The approximate cost of the cooling system is determined. |
| format |
Article |
| author |
Ihschenko, O.P. |
| author_facet |
Ihschenko, O.P. |
| author_sort |
Ihschenko, O.P. |
| title |
An autonomous system of a spent fuel pool cooling in WWER-1000 |
| title_short |
An autonomous system of a spent fuel pool cooling in WWER-1000 |
| title_full |
An autonomous system of a spent fuel pool cooling in WWER-1000 |
| title_fullStr |
An autonomous system of a spent fuel pool cooling in WWER-1000 |
| title_full_unstemmed |
An autonomous system of a spent fuel pool cooling in WWER-1000 |
| title_sort |
autonomous system of a spent fuel pool cooling in wwer-1000 |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2017 |
| topic_facet |
Проблемы современной ядерной энергетики |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/136034 |
| citation_txt |
An autonomous system of a spent fuel pool cooling in WWER-1000 / O.P. Ihschenko // Вопросы атомной науки и техники. — 2017. — № 2. — С. 117-123. — Бібліогр.: 8 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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| first_indexed |
2025-11-26T06:33:02Z |
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2025-11-26T06:33:02Z |
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| fulltext |
ISSN 1562-6016. PASТ. 2017. №2(108), p. 117-123.
UDC 621.039.586
AN AUTONOMOUS SYSTEM OF A SPENT FUEL POOL COOLING
IN WWER-1000
O.P. Ihschenko
South-Ukraine Nuclear Power Plant, Youznoukrainsk, Ukraine
E-mail: zihuatanehu@gmail.com
The issue of WWER-1000 spent fuel pool cooling in total blackout conditions is evaluated. A model of a spent
fuel pool for MELCOR computer code is developed. Basic information about a spent fuel pool construction is
shown. Basic data for a spent fuel pool cooling system calculations are given. A scheme of a spent fuel pool
autonomous cooling system as well as calculation results of its operation are provided. The analysis results of of the
autonomous cooling system operation is performed. The calculation of the autonomous cooling system equipment is
done. Necessary network parameters are defined. The approximate cost of the cooling system is determined.
INTRODUCTION
Loss of cooling water of spent fuel pool in a total
blackout was caused by uncontrolled temperature rising
in the spent fuel pool of the Fukushima nuclear power
plant during the course of a severe accident, that
happened on March 11, 2011. Another cooling system
of spent fuel pool was not provided.
The relevance of the loss of cooling water of spent
fuel pool problem underlines by statement that was
made on March 25, 2011 Council of the European
Union's about re-evaluation of safety of European
nuclear power plants on the basis of a comprehensive,
open risk assessment (“stress tests”). At its fifth meeting
to review the implementation of commitments under the
Convention on Nuclear Safety (414 April 2011),
Member countries of the Convention, “Fukushima-
Daiichi” a joint statement on the accident at the plant
indicated the need for a reassessment of nuclear safety
and the immediate implementation of additional
measures to improve NPP safety.
FORMULATION OF THE PROBLEM
The objectives of this research are the development
and modeling of autonomous water cooling system
cooling the spent fuel pool at the failure of the primary
cooling system, as well as determining the time in
which such a system must be put into operation in order
to prevent boiling of water in the spent fuel pool. It is
also necessary to take into account the most
conservative version of the emergency unloading from
the active zone, when the power of energy release from
fuel assemblies are maximized.
To success in the research necessary to develop a
computational model of the spent fuel pool and the
autonomous cooling system, to determine the time
before the start of boiling water in the cooling pool, as
well as the minimum necessary to determine the
parameters under which will operate the emergency
cooling system. The analysis used a conservative
assumption that the fuel assemblies are unloaded from
the active zone in the spent fuel pool after 13 days after
reactor shutdown (the minimum time necessary to
disassemble the reactor for unload fuel rods).
INITIAL CONDITIONS OF CALCULATIONS
The construction of the spent fuel pool is taken
identical with spent fuel pool on the unit No 3 SUNPP
with WWER-1000. The spent fuel pool consists of 4
sections: three cassette compartment with shelves
packed fuel assemblies constructed specifically for the
storage of spent fuel assembles and to install airtight
containers, and one that is a universal socket. Universal
socket can be used to install the cover with fresh fuel
assemblies. The division into three cassette
compartment allows you to carry out repair work in one
compartment, while fuel assemblies are placed in the
other two. Capacity of spent fuel pool is 563 cells for
fuel assemblies and 50 cells under the shipping cask.
Calculating the most conservative version of
accident because of high level of power ratio, assume
that the emergency uploading of active zone is done in
the cassette compartment number 3, that accommodates
110 fuel assemblies.
Initial data:
• the water temperature in the spent fuel pool
50 °C;
• initial water level 8.03 m;
• the total thermal power of fuel assemblies:
Compartment 1 = 1638.2 kW, Compartment 2 = 1492.2 kW,
Compartment 3 = 2151.3 kW;
• the total thermal power of fuel assemblies in an
emergency active zone unloading: Compartment
3 = 5689.2 kW.
• temperature at which the autonomous cooling
system starts to work 90 °C.
The volume of water, defined in the cassette
compartment, is calculated including the volume of
water displaced by spent fuel racks, fuel assembles, etc.
When calculating the volume of water displaced
following assumptions were made:
1) the amount of fuel assemblies, protective covers
in the shelves, and the failed fuel detection system was
calculated according to their geometrical dimensions;
2) was taken into the account in each compartment 2
spacer plates of 5 cm and a thickness of the base plate
6 cm;
3) when calculating the volume of the plates is taken
into account with a gap between the sections and sealed
shelving section with shipping casks (accepted model
20 cm) and perforation depending on the number of fuel
assemblies;
4) the volume of slats attached to the edges of covers
for a spacing between the covers, taken equal to the
volume of the two plates (compartment area 20 mm
thick) in the top and bottom covers.
THE NODALIZATION SCHEME OF THE
SPENT FUEL POOL
The behavior of the spent fuel pool is determined by
modeling his constructions, cooling water, the residual
energy of spent nuclear fuel by means of Account Code
MELCOR 1.8.5 [1].
The nodalization cheme of the spent fuel pool is
shown on the Fig 1. In this model spent fuel pool
represented by 22 control volumes, connected by 25
ways of flowing.
Control volumes CV476, 477, 478 are modeling the
lower part of the compartments of the spent fuel pool
the volume of water between the floor and the bottom
baseplate. CV486, 487, and 488 are part of the
compartment, where the racks are located directly,
shipping casks, support and spacer plate. Directly in the
modeled data volume capacity of the residual energy in
the form of fuel assemblies internal energy source via
packet control functions. Thus, according to the initial
conditions for the CV486 control function CF824 is
given the power of the internal power source, which is
equal to 2151.3 kW for CV487 CF814 equal to
1492.2 kW and CV488 CF804 equal to 1638.2 kW.
Modelling of the upper volume CV493 allows to
consider the overflow of water from section N 1 to
section N 2 during thermal expansion of the water when
the water level in the spent fuel pool is in the storage
mode. The possible overflow of water from the section
N 3 is modeling using FL315.
For including the hydrostatic pressure gradient and
the simulation of natural circulation processes in the
spent fuel pool upper part is divided into four height
control volume CV493, 494, 495, 496 for compartments
No 1, 2, and CV489, 490, 491, 492 For compartment
No 3.
When modeling of flow paths taken into account the
process of interfacial interaction, for this purpose in
each flow path was set interfacial friction factor of 0.01.
Ways of flowing FL314 and FL313 are modeling the
connection between the spent fuel pool and the
containment. With the ability to FL316 simulated water
overflow as a result of thermal expansion of water at a
level the spent fuel pool in overload mode.
Because of minor influence in the spent fuel pool
model conservatively, not simulated heat transfer from
the water to the spent fuel pool walls.
Fig. 1. The nodalization scheme of the spent fuel pool
AN AUTONOMOUS SYSTEM OF A
SPENT FUEL POOL COOLING
The spent fuel pool stationary is cooled by cooling
system which consists of three channels, each of them
includes a pump and heat exchanger. One of them
always active. The cooling water that circulates in the
space of the tubular heat exchangers is pumped by
separate pumps. Consequently, the power loss affects
the efficiency of the system, disabling not only the
cooling water storage pool pump system, but also makes
it impossible pumped cooling medium pumps. The
parameters of the system are regulated according to the
current water temperature in the spent fuel pool.
In an emergency, it proposed to activate the
autonomous system of a spent fuel pool cooling. The
scheme of the autonomous system of a spent fuel pool
cooling is shown in Fig. 2. The scheme is organized by
2 circuit. Inner loop stationary established inside the
reactor building and if necessary connected by flexible
hoses to a cell, the outer loop. A heat exchanger, pumps
and generators are delivered to the diesel engines are
provided with the compressed air cylinders and filled
the spent fuel pool if part of the water before the cooling
system connection evaporated.
In the nodalization scheme og the spent fuel pool the
autonomous system working is realized by supplying
water to the volume of CV476, 477, 478, which
corresponds to pipelines supplying cooling water from
pool cooling pumps. Water intake volume of organized
CV500, 502, 504. Volumes CV501, 503, 505 are
designed to improve the mixing of water in the
compartments.
Fig. 2. The scheme of the autonomous system of a spent fuel pool cooling
THE RESULTS OF CALCULATION WHILE
THE SPENT FUEL POOL COOLING IS
ORGANIZED
The results of calculation are shown in pictures: for
compartment 1 Figs. 3a, 3b, for compartment 2 in
Figs. 4a, 4b, the compartment 3 in Figs. 5a, 5b, 5c.
Pictures have a CVH designation, which means the
compartment number in the nodalization scheme.
Analysis of the results of calculations show that the
minimum required water flow in the autonomous
cooling system equal to 50 m
3
/h, for an emergency
active zone unloading 80 m
3
/h (see Fig. 5c).
The lowest temperature at which the boiling water in
at least one of the compartments of the spent fuel pool
was 65 °C, at this temperature begins boiling water in
the compartment 3 (see Fig. 5b), as well as that at 60 °C
water temperature in the compartment 3 is stabilized at
a value less than the saturation temperature (see Fig.
5a). Regarding the compartments 1 and 3, the
calculation results show that at a temperature of the
cooling water of 60 °C a decrease in temperature of the
water in these compartments (see Figs. 3a, 4a) and at a
temperature of cooling water 65 °C is observed
stabilization temperature of the water in these
compartments (see Figs. 3b, 4b). When simulating an
emergency active zone unloading 110 fuel assemblies in
the third compartment of the minimum required value of
the cooling water temperature is 40 °C (see Fig. 5c), and
the observed stabilization of the temperature at a value
less than the saturation temperature.
The cooling of the compartment 1 with temperature
of cooling water 60 С.
Fig. 3а. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 1 with temperature
of cooling water 65 С.
Fig. 3b. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 2 with temperature
of cooling water 60 С.
Fig. 4а. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 2 with temperature
of cooling water 65 С.
Fig. 4b. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 3 with temperature
of cooling water 60 С.
Fig. 5а. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 3 with temperature
of cooling water 65
С.
Fig. 5b. The line graph of the pool water temperature
changes in the spent fuel pool in time
The cooling of the compartment 1 with temperature
of cooling water 40 С when 110 fuel assembles are
uploaded into the compartment 3 after 13 days after
reactor shutdown.
Fig. 5c. The line graph of the pool water temperature
changes in the spent fuel pool in time
To realization the most conservative approach taken
in the model of temperature in the compartments of
achieving 90 C as the start point of the cooling water in
the compartments. The time to reach this temperature is
shown in Table.
The time until the temperature in the spent fuel pool
compartments 90 С
No of
compartment
The time until the temperature in the
compartments 90
0
С, s (h)
1 1.78861E+04 (4.96)
2 1.92257E+04 (5.34)
3 7.45940E+03 (2.07) 2.60920E+03(0.72)*
*Time in emergency unloading bay 3110 fuel assemblies on
the 13th day.
After the events at the Fukushima nuclear power
plant began more intensive study of the cooling
problems of the pools in total blackout. Various studies
involve issues such as exposure of the fuel assembly
with the boiling water, hydrogen evolution in the
process of accidents, damage fuel assemblies, damage
the floor of the spent fuel pool. Thus, in [2], including
the results obtained present the result of the beginning
of the boiling water in the spent fuel pool, which was
0.53 hours. Also in the “post-Fukushima” Development
Research Center “Kurchatov Institute” simulated severe
accident in the spent fuel pool during prolonged total
blackout using account code SOCRATES. Simulated
the following main processes for different valuesof the
residual energy [3]:
• dynamics of heating and boiling water in the spent
fuel pool;
• warm-up dynamics and the melting of spent
nuclear fuel in the spent fuel pool;
• generation of hydrogen as a result of oxidation of
the zirconium fuel assemblies and metal structures in
the spent fuel pool.
For calculations is used a spent fuel pool the same
with like in the unit N 1 of Balakovo NPP. The time for
beginning boiling of water in this work is 0.68 hours.
Also, in [4, 5] a diagram and description of the
passive fuel cooling system is shown. Implementing this
system complicated by the fact that the newly laid
pipeline communications, designed to transport water
from the spent fuel pool can interfere with the
movement of cargo handling machines; the distance
between the shelves and the wall, where it is planned to
place heat exchangers, is 675 mm at the bottom and
25 mm in the lateral parts. That may not be enough to
accommodate the heat exchangers between the shelves
and the walls of the spent fuel pool. It is necessary to
take into account the requirements of not to low the
boric acid concentration in the spent fuel pool in the
case of depressurization of the coolant circulation
circuit in the cooling system. And also do not forget
about the ALARA principle, after conducting these
works will lead to an increased dose loads on the
personnel who would conduct them.
CALCULATION OF HEAT EXCHANGERS
FOR THE SPENT FUEL POOL COOLING
WATER SYSTEM
Т 2
Т 4
Т 5
Т 1
Т 6
Т 7
Т 3
G 1
G 2
G 3
12
Fig. 6. The thermal schematic of cooling water system
for the spent fuel pool
The thermal schematic of cooling water system for
the spent fuel pool is shown in Fig. 6 – heat exchanger
cooling water of the spent fuel pool. 2 – heat exchanger
air-cooling water supplied to the spent fuel pool cooling
water.
T1 = 85 ºC outlet temperature of cooling water;
T2 = 35 ºC inlet temperature of the cooling water;
T3 = 85 ºC inlet temperature to the heat exchanger 2;
T4 = 90 ºC the temperature of the spent fuel pool
cooling water; T5 = 40 ºC temperature of cooled
water, which returns to the spent fuel pool; T6 = 29.3 ºC
the air temperature supplied to the cooling heat
exchanger 2; T7 = 60 ºC air temperature at the outlet
of the heat exchanger 2; G1 = 80 m
3
/h the rate of water
flow in the cooling water circulation loop; G2 = 80 m
3
/h
the rate of the cooling water flow to the spent fuel
pool; G3 air flow.
The temperature adopted in accordance with [6], as
the highest average temperature in the Mykolaiv region.
The equation for the heat balance [7] of the heat
exchanger 1 is
542211 TTCGTTCG pp ,
where Cp specific heat of water.
Accept for the design of the system
G1 = G2 = 22.2 kg/s.
Adopted for the heat exchanger 1 tube outer
diameter Do = 0.019 m tube wall thickness 0.001 m, the
inner diameter Din = 0.017 m, water velocity in the
tubes take w = 1.7 m/s.
Number of tubes in the tube bundle heat exchanger
is equal to
n
fw
G1 = 58,
where f the cross section area of one of the tube,
the density of water.
Because F1 and F2 are equal coefficients of heat
transfer for the heat exchanger 1 are
' '
1 2 2
e
12938.2
d
l W
Nu
m К
,
where of Nu Nusselt number; de equivalent
diameter; l water conductivity.
The heat transfer coefficient for the designed heater is
2
av avin
1 in w o 2 o
1
6830.6 ,
d dd
ln
d 2 d d
av
W
k
m Кd
where dav average diameter tubes; w thermal
conductivity of the wall material.
The average temperature difference in the heater
determined by the formula
2
sb tt
t
, as
b
s
t
1.7,
t
where sb tt , a bigger and a smaller temperature
difference (Fig. 7).
Δ
t b
Δ
t s
Т 5
Т 4
Т 1
Т 2
G
Т
Fig. 7. The process of heating water in a
countercurrent heater
The required heat transfer surface area of the heater
is:
tk
Q
F
= 135.8 m
2.
The length of the tube bundle is
t b
t s
nd
F
L
av
= 41.4 m.
With a length of tubing 3 m the number of turns is
equal to
14
3
L
Z .
Then the diameter of the envelope tube bundle is
Dt = 1.1076s(nZ)
0,4987
= 1 m,
where s = 1.8do step between the tubes.
The inner diameter of the heater body is
Din = Dt + 1.5s = 1.05 m.
The equation for the heat balance of the heat
exchanger 2 is
673231 TTCGTTCG a
pp ,
where Cp specific heat of water;
a
pC specific heat of
air.
From the heat balance equation G3 = 140.3 kg/s.
Adopted for the heat exchanger 2 tube outer
diameter Do = 0.019 to 0.001 m, the inner diameter of
tubing wall thickness Din = 0.017 m, water velocity in
the tubes take w = 1 m/s.
Number of tubes in the tube bundle heat exchanger
is equal to
n
fw
G1 = 98.
Coefficients of heat transfer for the heat exchanger 2
are
"
1 2
e
12938.2 .
d
l W
Nu
m К
The tubes in the heat exchanger design with fins
with a pitch of 0.006 m with a wall thickness of 0.001 m
and a rib height of 0.019 m. Then the number of Nusselt
adjusts for finning tubes surface [8].
"
2 2
e
43.38 ,
d
a W
Nu
m К
where Nu Nusselt number; de equivalent diameter;
l thermal conductivity of the water; a air
thermal conductivity.
The heat transfer coefficient for the designed heater is
2
av avin
1 in w o 2 o
1
64.94 .
d dd
ln
d 2 d d
av
W
k
m Кd
The average temperature difference in the heater
determined by the formula
і
b
sb
t
t
tt
t
ln
, as
b
s
t
1.7
t
,
where sb tt , a bigger and a smaller temperature
difference (Fig. 8).
Δ
tb
Δ
ts
Т 2
Т 3
Т 7
Т 6
G
Т
Fig. 8. The process of heating water in a current heater
The required heat transfer surface area of the heater
is:
tk
Q
F
= 4653 m
2.
The length of the tube bundle is
nd
F
L
av
= 27442 m.
With a length of tubing 5 m the number of turns is
equal to
5488.
3
L
Z
Then the diameter of the envelope tube bundle is
Dt = 1.1076s(nZ)
0.4987
= 21 m,
where s = 1.8do step between the tubes.
The inner diameter of the heater body is
Din = Dt + 1.5s = 21.05 m.
ECONOMIC CALCULATION OF THE
SYSTEM
Required cooling water heaters to ensure the
provision, which should ensure the flow rate of
140 kg/s. Fan Soler & Palau HCBT/4-900/H-XV5 axis
gives the flow rate of 15.5 kg/s, so 9 such units give the
required air flow. For convenience of construction and
operation of the heat exchangers 9 can be used with a
diameter of 2 m and a single fan or each vary their
number and size. The cost of one fan is currently
55596 UAH. The mass of material required for the heat
exchanger was 468 kg for the heat exchanger 1 body
(steel material 20), and 15444 kg for one group of heat
exchangers 2 bodies (steel material 20), as well as
261.3 kg for the heat exchanger 1 tubes (12X18H10T
material) and 19556.7 kg for heat exchangers 2 tubes
(copper material). Estimated cost of the material
required for the manufacture of heat exchangers
amounted to 24375 UAH for the heat exchanger 1 and
1863091 UAH for the heat exchanger 2, we introduce
the cost factor for manufacturing the heat exchanger is
equal to 3, then the price will be 73125 UAH and
5589273 UAH respectively. The pump unit K90/20 is
able to provide the required parameters in the system, it
cost 4897 UAH, subject to a reserve pump for each
circuit requires 4 of the pump. Total estimated value of
the overall system of pipelines, excluding costs
6182350 UAH.
CONCLUSIONS
The scheme of the autonomous cooling system of
the spent fuel pool is shown in Fig. 2, the work of the
system in nodalization scheme of the spent fuel pool is
implemented, the results of the calculations are shown
(see Figs. 3a, 3b, 4a, 4b, 5a, 5b, 5c). The time during
t b
t s
which the operation must be entered into the system is
defined (see Table). The situation with an emergency
active zone unloading in which the compartment 3 (see
Fig. 5b) is completely filled is calculated. To achieve
the aims nodalization scheme of the spent fuel pool has
been developed, as well as to determine the minimum
required parameters of the cooling system of the spent
fuel pool, minimum required cooling water flow is
50 m
3
/h, and the minimum required cooling water
temperature was 60 C, the most conservative variant of
these options amounted to 80 m
3
/h and 40 C,
respectively.
During the work calculations of heat exchangers and
network parameters are defined, necessary for the
implementation of the proposed water cooling system
storage pool under the most conservative version of the
accident.
This work reflects the situation with the real
distribution of power of the residual energy in the
compartments of the spent fuel pool, as well as the most
conservative version of the emergency uploading of
active zone is done in the cassette compartment N 3.
The results of calculation determines the required
parameters of the cooling system, which can be
obtained using a small centrifugal pumps, the most
cumbersome, despite the fin tubes, it is water cooling
unit with air, which is also, as the cooling water circuit
cooling pool can be installed permanently. In general,
such a system can be implemented at nuclear power
plants with WWER-1000.
The estimated cost of the system equipment
amounted to 6182350 UAH.
REFERENCES
1. MELCOR Computer Code Manuals. V. 2:
Reference Manuals. Version 1.8.5. 2000, 538 p.
2. Y.Y. Vorobiyov, A.L. Kotsuba. Analysis of a
severe accident in the spent fuel pool for VVER-1000
using code MELCOR 1.8.5 // Nuclear and Radiation
Safety. 2014, N 2 (62), p. 3-9
3. V.I. Skalozubov, V.N. Vashchenko, I.L. Kozlov,
S.V. Klevtsov. Severe accidents at nuclear power plants
with vessels nuclear reactors. Fundamentals of
modeling and analysis: Monograph. Odessa, 2015,
319 p.
4. A.V. Podoprigora, I.I. Sviridenko, D.V. Shevelev.
Passive system of emergency repair cooldown of
VVER-1000 // SevNTU Bulletin: Coll. Science.
pr. V. 119/2011. Series “Mechanics, energy and
ecology”. Sevastopol, 2011.
5. I.I. Sviridenko, D.V. Shevelev, S.S. Vibornov,
H. Haffaa. Using of thermosyphon heat exchanger
equipment in the passive heatsink // Safety Assurance of
NPP with VVER: Conference materials. EDO
“Gidropress”, 2013.
6. N.B. Vargaftik. Handbook of thermophysical
properties of liquids and gases. M.: “Nauka”, 1972,
721 p.
7. A.V. Korolev, G.P. Verhivker Heat-generating
installations using organic fuel. Odessa: ONPU, 2002,
46 p.
8. B.S. Petukhov, V.K. Shikov. Handbook heat
exchangers. M.: “Energoatomisdat”, 1987, v. 1, 560 p.
Article received 04.01.2017
АВТОНОМНАЯ СИСТЕМА ОХЛАЖДЕНИЯ БАССЕЙНА ВЫДЕРЖКИ
ОТРАБОТАННОГО ЯДЕРНОГО ТОПЛИВА НА АЭС С РЕАКТОРОМ ВВЭР-1000
О.П. Ищенко
Рассмотрена проблема охлаждения воды в бассейне выдержки при обесточивании. Построена
нодализационная схема бассейна выдержки, разработанная с помощью расчетного кода MELCOR.
Приведены исходные данные расчетов системы охлаждения и продемонстрирована схема автономной
системы охлаждения бассейна выдержки. Приведены результаты моделирования функционирования данной
системы. Проведен анализ полученных результатов моделирования. Выполнен расчет оборудования
системы охлаждения воды бассейна выдержки, определены необходимые параметры сети и
ориентировочная стоимость системы охлаждения.
АВТОНОМНА СИСТЕМА ОХОЛОДЖЕННЯ БАСЕЙНУ ВИТРИМКИ
ВІДПРАЦЬОВАНОГО ЯДЕРНОГО ПАЛИВА НА АЕС З РЕАКТОРОМ ВВЕР-1000
О.П. Іщенко
Розглянуто проблему охолодження води в басейні витримки при знеструмленні. Побудовано
нодалізаційну схему басейну витримки, що розроблена за допомогою розрахункового коду MELCOR.
Наведено вихідні дані розрахунків системи охолодження і продемонстровано схему автономної системи
охолодження басейну витримки. Наведено результати моделювання функціонування даної системи.
Проведено аналіз отриманих результатів моделювання. Виконано розрахунок обладнання системи
охолодження води басейну витримки, визначені необхідні параметри мережі і орієнтовна вартість системи
охолодження.
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