WP2.1: Pressurized Thermal Shock - nurisp.eu package 2.1: Pressurized Thermal Shock (PTS) Main...
Transcript of WP2.1: Pressurized Thermal Shock - nurisp.eu package 2.1: Pressurized Thermal Shock (PTS) Main...
WP2.1: Pressurized Thermal Shock
D. Lucas, P. Apanasevich, B. Niceno, C. Heib, P. Coste, M. Boucker, C. Raynauld,J. Lakehal, I. Tiselj, M. Scheuerer, D. Bestion
Work package 2.1: Pressurized Thermal Shock (PTS)
• Introduction (D. Lucas)• Improved model approaches (P. Coste)• Benchmark simulations on TOPFLOW-PTS (P. Apanasevich)• Conclusions and recommendations (D. Lucas)
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
Final question: Thermal loads on the RPV wall?
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Work package 2.1: Pressurized Thermal Shock (PTS)
Main achievements of the WP
• Improvement of model approaches for:– Turbulence models– Interfacial heat transfer models– 1D code WAHA for condensation induced water hammer
hot steam inlet
closed end
SLUG
slug head
The condensation induced water hammerexperiment by Martin et al. was simulated withthe WAHA code
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• Test of capabilities of CFD-codes for PTS– Benchmark on TOPFLOW-PTS experiments– Benchmark on COSI experiments– Validation on ROSA experiments
• RecommendationsROSA at Large Scale Test Facility
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Work package 2.1: Pressurized Thermal Shock (PTS)
Presentations
• Introduction (D. Lucas)
• Improved model approaches (P. Coste)
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
• Benchmark simulations on TOPFLOW-PTS (P. Apanasevich)
• Conclusions and recommendations (D. Lucas)
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Improved model approaches
TransAT ANSYS CFX 12.0 NEPTUNE_CFD
Formulation One-fluid Two-fluid Two-fluid
Turbulence (includingbuoyancy)
One-fluid k-ε(URANS or V-LES)
Shear Stress Transport (SST): combination of k-ε and k-ω)
Two-fluid k-ε(URANS or V-LES)
Wall Wall functions Wall functions Wall functions
Large interface
Level set AIAD detection based on the gas volume fraction αG
Interface recognition based on ∇αG
w/o reconstruction
Int. mom. transfer
Turbulent viscosity from one-fluid k-ε
Free surface drag Anisotropic friction
Mass transfer model
Scale Adaptative Interfacial transfer model
Hughes and Duffey Large Interface Model for condensation
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V-LES as tested in NURISP COSI calculations
• URANS (k-εεεε) calculation with two modifications
• A decrease of the turbulent viscosity based on the comparison between a constant filter scale ∆ input by the user and the integral length scale output from the k-ε equations (Johansen et al., 2004)
εεν µ
²;1min
233
k
kCCT
∆=εν µ
²kCT =
Turbulence
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• A consistent modification of the turbulent Reynolds number used in the closure laws
εk ε
( )∆= ,min LLt
Φ
−=
)(
)_(23
TransATsetlevel
or
CFDNEPTUNEphaseTwok
L
ε
21kut =
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AIAD free surface drag CFX 12.0
•Algebraic Interfacial Area Density framework (Egorov, 2004; Deendarlianto et al., 2012)
( ) 2D D Mix L GF C A U Uρ= −Drag force:
1=Gα
0=Gα
1=Gα
0=Gα
D,D DC ; A
D,FS FSC ; A
D,B BC ; AB
GB d
Aα6=
D
LD d
Aα6=
FS GA α= ∇
Mix G G L Lρ ρ α ρ α= +
Int. mom. transfer
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Bd
D B D,B FS D,FS D D,DC f C f C f C= + +Drag coefficient: f: blending functions
•Free surface drag coefficient (Höhne, 2009) [ ]2
2 G G L LD
Mix slip
CU
α τ α τρ
+=
2 2 2L,G L,G L,G
y,L,Gx,L,G z,L,GL,G L,G
FS FS FS
uu ux y z
x A y A z A
α α α
τ µ
∂ ∂ ∂ ∂∂ ∂∂ ∂ ∂ = ⋅ + ⋅ + ⋅ ∂ ∂ ∂
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Anisotropic free surface friction NEPTUNE_CFD
Normal surface direction: bubbles and droplets drags
Tangent plane : waves taken into account in roughness wall laws on liquid and gas sides
Int. mom. transfer
( )qk
LItrLIqk
nrqk
qkq uFuFJ ,,,
rrr−−=′ → α
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2*2*LLGG uu ρρ =
+= t
GG r
g
uyr
2*
12 ,min ββ
•Modelling of waves that can not be simulated
•Wind contribution (Charnock)
•Liquid turbulence contribution
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Scale Adaptative Interfacial transfer Model TransAT
Mass transfer
Interphase mass transfer term in Level Set topology equation : D / Dt Kφ φ= ∇
K m / ρ= &-> phase change velocity (m/s):
.
/ / . .Pr . Re Ren mt t t tK u m u C fρ ≡ =
Extension of the Surface Divergence approach :
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t t t t
• Banerjee et al. (2004): m=-1/2 with a turbulent Reynolds number taken in the core flow of the turbulence-generating phase
• TransAT (Lakehal and Labois, 2011): m=-1/4 with a turbulent Reynolds number taken right at the interface
validated on the NURISP calculations of three Lim et al. (1984) tests
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Two-phase CFD models CFX 12.0 and NEPTUNE_CFD
Mass transfer
Mass transfer term deduced from a heat balance at the interface
• CFX 12.0 TOPFLOW-PTS calculations: infinite
Condensation mainly controlled by the liquid side
( ) ( )12
1 HH
TThTTh GsatgeLsatle
−−+−
=Γ
geh
Gas side model (hge)
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• NEPTUNE_CFD 1.0.8: Jayalilleke (1969) wall law
• CFX 12.0 TOPFLOW-PTS calculations: Hughes and Duffey model
Liquid side model (hle)
• NEPTUNE_CFD 1.0.8: large interface model ✦
4121
,2
=νερ
π LLpLle aCh
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Large Interface Model for hle NEPTUNE_CFD
Mass transfer
Two free surface regimes : smooth and wavy
geh
Characterized by the liquid turbulence, from L-q diagram from Brochini and Peregrine, JFM 2001
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A wall function-like model for hlein large interface regions
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Bench: Steam Water STratified flow NEPTUNE_CFD and TransAT
geh
x
z
Outlet
0
1260 cm
10 cm
910 cm
MeasurementsInlet
Gas
Liquid
Wall
Wall
Case Freesurface (kg/s) (kg/s) (°°°°C) (m2.s-2) (m2.s-2) (m2.s-3) (m2.s-3)
•Co-current condensing flow•Rectangular channel •z dim: 30.5 cm
Lim et al. (1984) experiment
Lm& Gm& GT Lk Gk Lε Gε
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1 Smooth 0.657 0.041 111 2.8 10-4 0.36 3.9 10-4 6.1
2 Smooth/wavy 0.657 0.065 116 2.8 10-4 0.92 3.9 10-4 24
6 Wavy 1.44 0.065 116 1.3 10-3 0.92 4.1 10-3 24
8 Wavy 1.44 0.126 125 1.3 10-3 3.4 4.1 10-3 180
•TransAT 32x130•NEPTUNE_CFD 18x410, 36x820, 72x1640
CFD meshes: 2D
turbulence: URANS
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Bench: Steam Water STratified flow (cont.)geh
Smooth Transitional Wavy
TransAT URANS
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Smooth Transitional Wavy
NEPTUNE_CFD1.0.8
•URANS •default LIM
optionssmall Ret y+ from 5 (m8) to 20 (m2)
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Benchmarking on COSI 3.8 NEPTUNE_CFD and TransAT
geh
Vapor inlet(co-current runs)
Outlet
ECC liquid inlet
« Upstream »
« Downstream »
COSI 3.8: a test w/o weir
COSI: thermohydraulics conditions of a PWR PTS, scale: 1/100 volume
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Cold water (ECC)
Cold leg
Vapor inlet(co-current runs)
Weir
Downcomer
Downcomer
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COSI 3.8: sensitivity to the mesh NEPTUNE_CFD
geh
G1
G0 S1 A1S0
S1 G1 S2 A2
MeshNb of cells
Гp/Гt,exp
G0S0A01.58 105
0.928
G0S1A16.40 105
0.931
G1S2A2 0.918
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S2
S3
G1S2A22.21 105
0.918
G1S3A2 0.928
G1S3A35.43 105
0.931
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COSI 3.8: TransAT meshgeh
Cartesian grid
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Cross section:37x37 cells
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COSI 3.8: URANS or V-LES NEPTUNE_CFD and TransAT
geh
12
3
4
x= -0.05 x= -0.3 x= -0.885x= -0.21N
orm
aliz
ed h
eigh
t
12 3
4
TransAT
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Nor
mal
ized
hei
ght
0,4 0,6 0,8 1
00,
20,
40,
60,
8N
orm
aliz
ed h
eigh
t
0,4 0,6 0,8 1
00,
20,
40,
60,
8expNCFD VLESNCFD URANS
0,4 0,6 0,8 1
00,
20,
40,
60,
8
0,4 0,6 0,8 1
00,
20,
40,
60,
8
12
3
4
x= -0.05 x= -0.3 x= -0.885
x= -0.21
Nor
mal
ized
hei
ght
NEPTUNE_CFD1.0.8
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COSI 3.8: URANS or V-LES (cont.) NEPTUNE_CFD and TransAT
geh
5 6 7 8
8 567
x= +0.52 x= +0.37 x= +0.145 x= +0.065 N
orm
aliz
ed h
eigh
t
TransAT
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Nor
mal
ized
hei
ght
0,4 0,6 0,8 1Normalized temperature
00,
20,
40,
6N
orm
aliz
ed h
eigh
t
0,4 0,6 0,8 1Normalized temperature
00,
20,
40,
6
0,4 0,6 0,8 1Normalized temperature
00,
20,
40,
6
0,4 0,6 0,8 1Normalized temperature
00,
20,
40,
6
8 567
x= +0.52 x= +0.37 x= +0.145 x= +0.065
Nor
mal
ized
hei
ght
NEPTUNE_CFD1.0.8
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COSI 3.8: TransAT and NEPTUNE_CFDgeh
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COSI 3.8: TransAT and NEPTUNE_CFD (cont.)geh
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Work package 2.1: Pressurized Thermal Shock (PTS)
Presentations
• Introduction (D. Lucas)
• Improved model approaches (P. Coste)
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
• Benchmark simulations on TOPFLOW-PTS experiments (P. Apanasevich)
• Conclusions and recommendations (D. Lucas)
21
TOPFLOW-PTS Experiments
Pressure Vessel
TOPFLOW-PTS facility
IR cameraThermo lances
High-speed camera
WMS
Cold leg (CL)
Pump simulator (PS) Downcomer
Reference plant:• EDF CPY 900 MWe PWR• Scale 1:2.5• Air-water tests � without condensation• Steam-water tests � with condensation
TOPFLOW-PTS facility
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Numerical Grids
Neptune_CFD:• IRSN-EDF grid• 594,000 cells• 1,500,000 cells
ANSYS FLUENT:• HZDR grid• 865,000 cells
ANSYS CFX:• HZDR grid• 1,450,000 cells
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CFD Codes
• Neptune_CFD 1.0.8 (IRSN, CEA):– Air-water test � IRSN– Steam-water test � CEA– Two-fluid model – Turbulence: k-ε model (for each phase) – Large Interface Method (LIM)– Transient
• CFX 12.0 (HZDR):• CFX 12.0 (HZDR):– Two-fluid model– Turbulence: SST (for each phase)– Algebraic Interfacial Area Density Model (AIAD)– Steady state/transient
• FLUENT 12.0 (PSI):– One momentum equation & Volume Of Fluid (VOF) approach – Turbulence: LES approach (Smagorinsky model)– Transient
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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SimulationsSimulations ofof Air Air –– WaterWater ReferenceReference CaseCase
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Boundary Conditions
� Water level in the cold leg: 50%� MECC, Re_ECC=62700, θECC=0
� MPS_in, Re_PS=42200, θPS=1� MECC/MPS_in=1.7� MDC=MECC + MPS_in (out)� θAir=0.4
HZDR IRSN PSI
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ECC Jet Behaviour
� ANSYS CFX � Neptune_CFD� ANSYS FLUENT � Exp., HS camera
HZDR IRSN PSI
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Cold Leg: Water Temperature
0.0
0.1
0.2
0.3
0.4
0.5
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA1 Temperature Profiles Upstream from ECC injection
CFXNCFDFLUENTExperimentMeasurement error
0.0
0.1
0.2
0.3
0.4
0.5
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA2 Temperature Profiles Upstream from ECC injection
CFXNCFDFLUENTExperimentMeasurement error
LA2
LA4
LA3
LA1θ, [-] θ, [-]
0.0
0.1
0.2
0.3
0.4
0.5
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA4 Temperature Profiles Upstream from ECC injection
CFXNCFDFLUENTExperimentMeasurement error
0.0
0.1
0.2
0.3
0.4
0.5
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA3 Temperature Profiles Upstream from ECC injection
CFX
NCFD
FLUENT
Experiment
Measurement error
HZDR, IRSN, PSI
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Cold Leg: Bottom Wall Temperature� ANSYS FLUENT � Neptune_CFD
1
0.8
0.6
0.4
0.2
0
� ANSYS CFX
� ExperimentIR camera
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Downcomer
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-0.05 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35
θ, [
-]
ζ, [-]
DCLA3 Temperature Profiles
CFXNCFDFLUENTExperimentMeasurement error
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-0.05 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35
θ, [
-]
ζ, [-]
DCLA1 Temperature Profiles
CFXNCFDFLUENTExperimentMeasurement error
DCLA1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.05 0.10 0.15 0.20 0.25 0.30 0.35
θ, [
-]
ζ, [-]
DCLA20 Temperature Profiles
CFXNCFDFLUENTExperimentMeasurement error
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.05 0.10 0.15 0.20 0.25 0.30 0.35
θ, [
-]
ζ, [-]
DCLA17 Temperature Profiles
CFXNCFDFLUENTExperimentMeasurement error
ζ, [-]ζ, [-]DCLA1
DCLA3
DCLA17
DCLA20
HZDR, IRSN, PSI
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SimulationsSimulations ofof SteamSteam –– WaterWater ReferenceReference CaseCase
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Boundary Conditions
ECCPS_in
DC_out
Steam_out
PS_out
Steam_in
DC
PS
ECCPS_in
DC_out
Steam_out
PS_out
Steam_in
DC
PS
Experiment
� Water level in the cold leg: 50%� MECC, Re_ECC=325,000, θECC=0
� MPS_in, Re_PS=234,000, θPS_in=1� MECC/MPS_in=1.7� MDC=MECC + MCond (out)� MPS_out=MPS_in
� θSteam=1
HZDR PSI CEA
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Modeling of Direct Contact Condensation
• Neptune_CFD 1.0.8 (CEA):– Coste and Laviéville (2009)
� for smooth flows (Lakehal et al. 2008)
� for wavy flows
121 1 3 432 2 40 35 0 3 2 83 2 14t t t
t
K. Pr Re . . Re . Re
u
− − = −
1182
tt
KPr Re
u
−−=
• FLUENT 12.0 (PSI):– Hughes and Duffey (1991)
• CFX 12.0 (HZDR):– Hughes and Duffey (1991)
1 12 42
tt
KPr Re
u π− −
=
1 12 42
tt
KPr Re
u π− −
=
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Cold Leg
LA2
LA4
LA30
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0.50 0.60 0.70 0.80 0.90 1.00
η, [
-]
θ, [-]
LA1 Temperature profile Upstream from ECC injection
CFX_refinedNCFD_coarseNCFD_refinedFLUENT_coarse
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA2 Temperature profile Downstream from ECC injection
CFX_refinedNCFD_coarseNCFD_refinedFLUENT_coarse
LA1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA4 Temperature profile Downstream from ECC injection
CFX_refinedNCFD_coarseNCFD_refinedFLUENT_coarse
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.5 0.6 0.7 0.8 0.9 1.0
η, [
-]
θ, [-]
LA3 Temperature profile Downstream from ECC injection
CFX_refinedNCFD_coarseNCFD_refinedFLUENT_coarse
HZDR PSI CEA
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Cold Leg
θ=0.875
Neptune_CFD ANSYS CFXANSYS FLUENT
1FluentFluent
Fluent
ΓΓ = =Γ
% 1.73CFXCFX
Fluent
ΓΓ = =Γ
%2.25NCFDNCFD
Fluent
ΓΓ = =Γ
%
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Downcomer
HZDR PSI CEA
Neptune_CFD (refined grid):• Homogeneous temperature• Homogeneous temperature• θmin=0.936• θmax=0.946• ∆θ=0.01
ANSYS CFX:• Inhomogeneous temperature• Cold water plume• θmin=0.638• θmax=0.791• ∆θ=0.153 ANSYS FLUENT:
• Homogeneous temperature• θmin=0.881• θmax=0.962• ∆θ=0.081
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
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Work package 2.1: Pressurized Thermal Shock (PTS)
Presentations
• Introduction (D. Lucas)
• Improved model approaches (P. Coste)
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
• Benchmark simulations on TOPFLOW-PTS (P. Apanasevich)
• Conclusions and recommendations (D. Lucas)
37
Work package 2.1: Pressurized Thermal Shock (PTS)
Conclusions and Recommendations• Clear benefits of a multi-scale analysis of thermal-hydraulic issues:
– condensation induced water hammer investigated by CFD (NURESIM) and 1D WAHA code
– coupled system code – CFD simulation for ROSA
• Clear progress for two-phase PTS simulations with CFD– NEPTUNE_CFD with URANS-LIM and TransAT with LEIS could simulate COSI test
and several tests of Lim et al. including smooth interface and wavy interface– but: pre-test simulation of steam-water TOPFLOW-PTS experiments showed clear
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
– but: pre-test simulation of steam-water TOPFLOW-PTS experiments showed clear deviations between the results obtained by different codes and models(no results with TransAT, since the data are proprietary and thus not shared with ASCOMP)
Conclusions and Recommendations• Further investigations are necessary to explain and minimize the inconsis-
tencies between the codes and to identify the best models � post test simulations on TOPFLOW-PTS steam-water experiments (now available)
• Turbulence modeling of interfacial turbulent flows should be further improved and validated for flows with wavy interface and condensation.
38
Work package 2.1: Pressurized Thermal Shock (PTS)
Conclusions and Recommendations (cont.)• The modeling of interfacial friction in case of the two-fluid URANS approach
should be further improved – especially for waves smaller than the grid size.• Dedicated experimental data or DNS is needed to consider the influence of
heat and mass transfer on friction and turbulence.• Direct contact condensation approaches in TransAT (LEIS) and
NEPTUNE_CFD (URANS with LIM) seem to be applicable for PTS, but validation against TOPFLOW-PTS steam-water experiments should be
NURISP SECOND OPEN SEMINARApril 2-3, 2012, Karlsruhe
validation against TOPFLOW-PTS steam-water experiments should be done as a next step.
• Benchmarking of different codes and models should be done since it provides valuable information on the strengths and weaknesses of the single approaches.
• Before reactor application for PTS simulation, it is recommended to validate a frozen version of a modelling approach at least on the following validation base: air-water Fabre et al. data, Lim et al. (1984), jet impingement data (Bonetto and Lahey, Iguchi experiments) and COSI tests. TOPFLOW-PTS and ROSA experiments should be added in the future.
39