Embed Size (px)
Citation preview
© SCK�CEN, 2018
Ongoing RELAP5-3D-related activities at SCK•CEN
Diego CastellitiSCK•CEN
IRUG meeting 2018, 3-4 May 2018, Idaho Falls
1
© SCK�CEN, 2018
Contents
l MYRRHA plant main features
l MYRRHA pre-licensing activities: safety studies
l MYRRHA pre-licensing activities: experiments
2
© SCK�CEN, 2018
MYRRHA plant main features – Main purposes
l MYRRHA: Multi-purpose hYbrid Research Reactor for High-tech Applications at SCK•CEN
3
l Pool-type Accelerator Driven System (ADS) with ability to operate also as critical reactor
l Liquid Lead-Bismuth Eutectic (LBE) as primary coolant
l MYRRHA project recognized as high priority infrastructure for nuclear research in Europe
MYRRHA
Minor Actinides transmutation demonstrator
Flexible fast-spectrum irradiation
facility
ADS demonstrator GEN-IV European Technology Pilot
Plant (ETPP)
© SCK�CEN, 2018
MYRRHA plant main features – Plant overview
l MYRRHA: accelerator driven system (ADS)
ISOL@Myrrha
4
© SCK�CEN, 2018
MYRRHA plant main features – Fuel pin and fuel assembly
l MOX fuel, 30% wt. Pu
l Fuel pin with wire spacer
l Less vibrations
l Easier to fabricate and mount
l Better for small P/D (otherwise
too thick)
l Active length: 65 cm
5
l 127 pins per Fuel Assembly
l Hexagonal lattice
l Closed structure
l Wrapper enclosing pin bundle
l Total length: ~2.5 m
l Flow rate: 71.4 kg/s
© SCK�CEN, 2018
MYRRHA plant main features – Core layout
6
15 / 28
17 / 28
19 / 27
20 / 2721 / 27
21 / 26
23 / 25
26 / 21
27 / 20
28 / 17
28 / 19
27 / 19
28 / 1527 / 13
27 / 14
27 / 12
26 / 1325 / 12
21 / 13
19 / 13
17 / 15
16 / 16
15 / 1715 / 18
14 / 19
13 / 20
12 / 2113 / 21
12 / 25
12 / 26
14 / 2713 / 26
13 / 27
20 / 20
20 / 21
21 / 20
21 / 19
19 / 20
20 / 19
19 / 21
18 / 2118 / 22
19 / 22
18 / 20
21 / 21
20 / 22
22 / 20
22 / 19
22 / 18
21 / 1820 / 18
19 / 19
18 / 2319 / 23
20 / 23
21 / 22
22 / 21
22 / 17
23 / 17
23 / 18
23 / 19
23 / 20
17 / 23
21 / 17
20 / 17
19 / 18
18 / 19
17 / 20
17 / 21
17 / 22
17 / 27
18 / 2718 / 26
16 / 27
17 / 26
15 / 27
19 / 26
19 / 25
18 / 25
17 / 25
16 / 26
19 / 2420 / 24
20 / 25
20 / 2618 / 24
17 / 24
16 / 25
15 / 2613 / 24
13 / 25
14 / 24
14 / 2313 / 23
14 / 25
15 / 24
15 / 23
15 / 2214 / 22
13 / 22
14 / 26
15 / 25
15 / 2116 / 21
16 / 22
16 / 2316 / 24
14 / 21
16 / 17
16 / 18
17 / 17
17 / 16
15 / 19
17 / 18
16 / 19
18 / 17
18 / 16
18 / 15
14 / 2015 / 20
16 / 20
17 / 19
18 / 18
19 / 15
19 / 1619/ 17
23 / 13
23 / 1422 / 13
22 / 14
21 / 1421 / 15
22 / 15
24 / 14
23 / 15
25 / 13
21 / 1622 / 16
23 / 16
24 / 15
25 / 14
20 / 16
20 / 14
20 / 15
27 / 1726 / 16
27 / 15
26 / 17
25 / 1725 / 18
26 / 18
25 / 16 27 / 18
26 / 15
25 / 1926 / 19
24 / 19
26 / 14
25 / 15
24 / 16
24 / 17
24 / 18
24 / 23
25 / 22
23 / 23
24 / 22
23 / 24
22 / 2422 / 25
22 / 23
25 / 21
24 / 21
23 / 22
26 / 20
25 / 20
24 / 20
23 / 21
22 / 22
21 / 23
21 / 24
21 / 25
24 / 13 27 / 16
13 / 2812 / 2714 / 28
12 / 2412 / 23
12 / 22
13 / 19
14 / 18
18 / 14
19 / 14
20 / 13
21 / 12
22 / 12
24 / 12
23 / 12
26 / 1228 / 13
28 / 14
28 / 16
28 / 18
27 / 21
26 / 22
25 / 23
24 / 24
22 / 26
19 / 28
18 / 28
16 / 28
1 Spallation Target 72 FA
6 IPS6 Abs. Devices
84 Dummy (LBE)42 Reflector (Be)
15 / 28
17 / 28
19 / 27
20 / 2721 / 27
21 / 26
23 / 25
26 / 21
27 / 20
28 / 17
28 / 19
27 / 19
28 / 15
27 / 13
27 / 14
27 / 12
26 / 1325 / 12
21 / 13
19 / 13
17 / 15
16 / 16
15 / 1715 / 18
14 / 19
13 / 20
12 / 2113 / 21
12 / 25
12 / 26
14 / 2713 / 26
13 / 27
20 / 20
20 / 21
21 / 20
21 / 19
19 / 20
20 / 19
19 / 21
18 / 2118 / 22
19 / 22
18 / 20
21 / 21
20 / 22
22 / 20
22 / 19
22 / 18
21 / 1820 / 18
19 / 19
18 / 23
19 / 23
20 / 23
21 / 22
22 / 21
22 / 17
23 / 17
23 / 18
23 / 19
23 / 20
17 / 23
21 / 17
20 / 17
19 / 18
18 / 19
17 / 20
17 / 21
17 / 22
17 / 27
18 / 27
18 / 26
16 / 27
17 / 26
15 / 27
19 / 26
19 / 25
18 / 25
17 / 25
16 / 26
19 / 24
20 / 24
20 / 25
20 / 2618 / 24
17 / 24
16 / 25
15 / 2613 / 24
13 / 25
14 / 24
14 / 2313 / 23
14 / 25
15 / 24
15 / 23
15 / 2214 / 22
13 / 22
14 / 26
15 / 25
15 / 21
16 / 21
16 / 22
16 / 23
16 / 24
14 / 21
16 / 17
16 / 18
17 / 17
17 / 16
15 / 19
17 / 18
16 / 19
18 / 17
18 / 16
18 / 15
14 / 2015 / 20
16 / 20
17 / 19
18 / 18
19 / 15
19 / 1619/ 17
23 / 13
23 / 1422 / 13
22 / 14
21 / 14
21 / 15
22 / 15
24 / 14
23 / 15
25 / 13
21 / 16
22 / 16
23 / 16
24 / 15
25 / 14
20 / 16
20 / 14
20 / 15
27 / 1726 / 16
27 / 15
26 / 17
25 / 17
25 / 18
26 / 18
25 / 16 27 / 18
26 / 15
25 / 19
26 / 19
24 / 19
26 / 14
25 / 15
24 / 16
24 / 17
24 / 18
24 / 23
25 / 22
23 / 23
24 / 22
23 / 24
22 / 24
22 / 25
22 / 23
25 / 21
24 / 21
23 / 22
26 / 20
25 / 20
24 / 20
23 / 21
22 / 22
21 / 23
21 / 24
21 / 25
24 / 13 27 / 16
13 / 2812 / 2714 / 28
12 / 2412 / 23
12 / 22
13 / 19
14 / 18
18 / 14
19 / 14
20 / 13
21 / 12
22 / 12
24 / 12
23 / 12
26 / 1228 / 13
28 / 14
28 / 16
28 / 18
27 / 21
26 / 22
25 / 23
24 / 24
22 / 26
19 / 28
18 / 28
16 / 28
108 FA4 IPS6 CR (buoyancy)3 SR (gravity)
48 Dummy (LBE)42 Reflector (Be)
l Smaller core (72 FAs)
l Lower power (75 MW)
l No safety rods requiredl Keff = 0.95 à improved safety
l High and hard flux in core center à MA transmutation
l Proton source + window required
l High peaking factors à Peaked temperature profiles
l Larger core (108 FAs)
l Higher power (100 MW)
l Safety rods required
l Lower and softer neutron flux in core center
l No external source required
l Lower peaking factors
l Operating experience
© SCK�CEN, 2018
MYRRHA plant main features – Primary cooling system
l 4 Primary Heat eXchanger (PHX)
l 2 Primary Pumps (PPs)
7
l Primary system: completely enclosed in primary vessel (pool-type)
l Cold plenum separated from hot plenum by Diaphragml Above LBE free surface: Nitrogen layer
Lower plenum: 270 °C
Core: 100 MW
Upper plenum: 325 °C
A
B
C
D
EH
© SCK�CEN, 2018
MYRRHA plant main features – Primary cooling system
l Reactor layout
l Vessel
l Cover
l Core barrel and Multi-functional
plugs
l Above Core Structure
l Cradle, Core Restraint System,
beam line and window target
l Si-doping units, Mo-irradiation
units, control rods and safety rods
l Primary Heat Exchangers
l Primary Pumps
l In-Vessel Fuel Handling Machines,
Fuel Transfer Devices, Failed Fuel
Detection Devices, Extraction
Pumps
l Diaphragm and support structure
l Reactor pit, Reactor Vessel
Auxiliary Cooling System
8
© SCK�CEN, 2018
MYRRHA plant main features – STCS
l MYRRHA Secondary Cooling System (SCS):l Four independent SCSs loops operated at 16 bar, 200 °C
9
Saturated water, 200 °C
Two-phase mixture, x ~ 0.3, a ~ 0.9
l First sub-loop:l PHXl Steam Separatorl Feedwater Pump
Condensed water, 200 °C
Saturated steam, 200 °C
l Second sub-loop:l Steam Linel Aero-Condenserl Condensate Return Line
l Tertiary system: heat to external environment through AC
© SCK�CEN, 2018
MYRRHA plant main features – Operation conditions
l Normal operation à Plant operating in forced circulation
l Power: 110 MW (maximum)l 100 MW à core powerl 10 MW à additional heat sources:
l In Vessel Storage Tank (IVST)l Po decay heatl Pump powerl g heatingl Spallation target power
10
Operating conditions
l Accidental conditions à Plant able to remove Decay Heat in passive mode (natural circulation)
l Two systems to accomplish DHRfunction:l DHR-1: STCS operating in passive
mode (if required)l DHR-2: Reactor Vessel Auxiliary
Cooling System (RVACS)
© SCK�CEN, 2018
MYRRHA plant main features – Reactor Power Program
l MYRRHA: Material Testing and Demonstrator Reactor à high degree of flexibility required in terms of operational power
11
180
200
220
240
260
280
300
320
340
360
380
0 10 20 30 40 50 60 70 80 90 100
Tem
pera
ture
(°C)
Power (%)
Reactor power program
Core average LBE outlet temperature
PHX LBE inlet temperature
PHX LBE outlet temperature
SCS water temperature
l Power program concept:l Primary and Secondary mass
flow rate constant at any power load
l SCS pressure and temperature constant at any power load (16 bar, 200 °C)
l Primary System temperatures and PHX outlet quality varyingwith power load
l High SCS pressures at partial loads avoided!
© SCK�CEN, 2018
MYRRHA pre-licensing activities: safety studies
l MYRRHA plant main features
l MYRRHA pre-licensing activities: safety studies
l MYRRHA pre-licensing activities: experiments
12
© SCK�CEN, 2018
MYRRHA pre-licensing activities – RELAP5-3D model
l RELAP5-3D MYRRHA plant model:
l 2518 volumes, 2590 junctions
l All cooling systems (primary, secondary, tertiary) simulated
l Main control systems (Control Rods, secondary pressure) included
13
Core Pumps + Primary
Heat Exchangers
Primary System
Secondary +
Tertiary Cooling
System (x4)
© SCK�CEN, 2018
MYRRHA pre-licensing activities – RELAP5-3D model
14
l Main steady state results reported:
l Good agreement between code-calculated values and design valuesl Limited differences due to different LBE physical properties (mainly Cp)
l Maximum clad temperature ~470 °Cl Maximum fuel temperature ~1600 °C (low value due to low linear power
~110 W/cm)
Parameter Unit RELAP5-3D value Reference value Error %Active core mass flow rate kg/s 7719.3 7711.2 0.10
Total primary system mass flow rate kg/s 13833.6 13800.0 0.24Core inlet temperature °C 266.0 270.0 -1.48
Core average outlet temperature °C 351.7 360.0 -2.30Average core temperature difference °C 85.7 90.0 -4.78
FA friction pressure losses Pa 196397 200000.0 -1.80PP head Pa 311571 300000.0 3.86
SCS first sub-loop mass flow rate kg/s 45.9 47.0 -2.34PHX SCS lower head pressure Pa 1603210.0 1600000.0 0.20
PHX water outlet quality - 0.3 0.3 ~0
© SCK�CEN, 2018
MYRRHA pre-licensing activities: safety studies – Transients
15
MYRRHA transient safety studies based on enveloping Initiating Events
Loss Of Forced Flow Vessel BreakReactivity Insertion Accident
Primary Heat Exchanger Tube
Rupture
l Transients simulated using reference MYRRHA RELAP5-3D modell Appropriate boundary conditions assumed to represent enveloping conservative
cases
l MYRRHA entered pre-licensing phase (contacts with Belgian Safety Authority started)
© SCK�CEN, 2018
MYRRHA pre-licensing activities – LOFF
l Reference envelope LOFF transient: Loss Of Offsite Power with double locked rotor
16
l Unprotected transient: limit reached after ~17 sl Protected transient: safety criterion well respected
© SCK�CEN, 2018
MYRRHA pre-licensing activities – RIA
l Reactivity insertion caused by several reasons:l Water ingress
l Core compaction
l Accidental control rod ejection or withdrawal
l MYRRHA official RELAP5-3D model modified:l Secondary Cooling System removed
l Primary System reduced to core region
l Core split in 18 channels: different fuel batch à different gap conductance and NKfeedbacks
l Conservative case in terms of pin conductivity, thermal expansion and reactivity feedbacks:l Maximum step-type reactivity insertion: 211 pcm
l Maximum slope-type reactivity insertion: 109 pcm/s
17
© SCK�CEN, 2018
MYRRHA pre-licensing activities: experiments
l MYRRHA plant main features
l MYRRHA pre-licensing activities: safety studies
l MYRRHA pre-licensing activities: experiments
18
© SCK�CEN, 2018
MYRRHA pre-licensing activities – HEXACOM
l Heat EXchanger At COMplot (HEXACOM): two-phase pressurized water loop simulating MYRRHA PHX and SCSl Maximum power: 100 kW
l Design pressure: 25 bar
l Main objectives:l Investigate PHX configurations heat transfer performances
l Develop and validate HTC correlations for HX bundles in LBE
l Improve knowledge on two-phase phenomena at p < 20 bar
l Obtain experimental databases for model development
l Study two-phase phenomena in support of MYRRHA design
19
l Facility commission foreseen for end 2018
© SCK�CEN, 2018
MYRRHA pre-licensing activities – HEXACOM
l HEXACOM RELAP5 model for pre-tests
20
#1
PIPE100
#1
PIPE90
#1
PIPE110
#1PIPE120
#1BRANCH
80#1
BRANCH
125
#2 PIPE 130 #2 PIPE 132 #2 PIPE 134
V-724#2 VALVE 135
#2 PIPE 136
#2 PIPE138
#2 PIPE 144#2 PIPE 230
#3 BRANCH 240#3 BRANCH 239
#3 PIPE 320#3 PIPE 321#3 PIPE 322
#3 BRANCH 200#3 BRANCH 202 #3 BRANCH 203 #3 BRANCH 204
#3 PIPE 250
#3 PIPE 210
#4 BRANCH 260#4 TMDPVOL 261
#4 TMDPVOL 208#4 TMDJUN 209
#5 PIPE 190#5 PIPE 188
#1 PIPE 070
V-710#5 VALVE 187
#5 PIPE 186
#5 PIPE 184
#5 PIPE 182
V-719#5 VALVE 181
#5 PIPE 180
#5 TMDJUN 001
#0 PIPE 006
V-720#0 VALVE 007
#0 BRANCH 008#0 PIPE 009
V-736#0 VALVE 010
PIPE
013
V-714#0 VALVE 014
#0 PIPE
015
#0 PIPE 017 #0 PIPE 019 #0 PIPE 021
#0 PIPE 011
V-722#0 VALVE 020
#0 PIPE 025#0 PIPE 023
#0 PIPE 030#0 PIPE 032
V-716#0 VALVE 033
#0
PIPE 034 #6 TMDPVOL 834
#6 PIPE 836
#4 TMDJUN 835
#6 BRANCH 837
#6 BRANCH 838
#6
PIPE 840
#6 TMDPVOL 860#6 BRANCH 850
l Full power: as expectedl Partial loads: instabilities in
vertical line PIPE 138l Flow regime transitions: bubbly-
slug and slug-annular
l 0 à 40%, 70% à 100%: stablel 40% à 70%: unstable (slug ßà annular)l ~5%: unstable (bubbly ßà slug)l Instabilities noted in MYRRHA
model as well!
© SCK�CEN, 2018
MYRRHA pre-licensing activities – E-SCAPE
l European SCAled Pool Experiment (E-SCAPE): thermal hydraulic 1/6-scale model of the MYRRHA primary system
l Main objective: represent 3-D temperature and velocity fields (convection patterns, flow mixing, stratification)
l Power: 10 kW
21
l Two main working conditions:l Forced circulationl Natural circulation
l Correct temperature increase!
l Test matrix:l Full/reduced power operationl Single/multiple PHX or pump failure
l First steady-state tests recently finalized!
© SCK�CEN, 2018
MYRRHA pre-licensing activities – E-SCAPE
l E-SCAPE RELAP5-3D model for pre-tests
22
701711
702
703705707
713713717
738736733
708
723
724
Pump726
V-731
V-735 V-744V-740
V-706
V-716
749
786
776
746
727
792
712
743
60
901 905
945
944
902
902
906
907
909 910 912913 915 916
918 920924
921
925
926
937940
931
928Pump930
V-935
V-939
941942
936
980981982
987989
923
10
20 21270 630320
300
280
16
650
791790
797
783
732
660
799
260330
60
61
620
61
A-loop B-loop
Vessel
CFDdomain
Upper plenum
CFD domain Upper plenum
CFD domain Lower plenum
l Model built to pre-test system performances and data post-testl Initially developed as RELAP5-
3D stand-alonel Coupling with ANSYS-FLUENT
à Two CFD domains includedl Transient tests post-tests to be
finalized by April 2019 (EU H2020-MYRTE project)
l Loss Of Forced Flow pre-test simulation (MYRRHA vs. E-SCAPE)
© SCK�CEN, 2018
Conclusions
23
l MYRRHA plant currently under development at SCK•CENl Pre-licensing contact with Belgian Safety Authority startedl Several safety studies deliveredl Ongoing R&D program to better issue remaining open items
l RELAP5-3D: tool selected for design support and safety analysisl MYRRHA reference modell Pre- and post-test studies on experimental facilities à Contribution to code
validation:l Lead-Bismuth Eutectic as primary coolantl Pool-type reactors 3-D velocity and temperature fieldsl Low pressure ( < 16 bar) applications
