Transcript ARIES: Fusion Power Core and Power Cycle Engineering

ARIES-AT Blanket and Divertor Design
Presented by A. R. Raffray1
Contributors: L. El-Guebaly2, S. Malang3, I. Sviatoslavsky2,
M. S. Tillack1, X. Wang1, and the ARIES Team
1University
of California, San Diego, 460 EBU-II, La Jolla, CA 92093-0417, USA
2University of Wisconsin, Fusion Technology Institute, 1500 Engineering Drive, Madison, WI 53706-1687, USA
3Forschungszentrum Karlsruhe, Postfach 3640, D-76021 Karlsruhe, Germany
Japan-US Workshop on Fusion Power Plants and Related Advanced
technologies with participation of EU
University of Tokyo, Japan
March 29-31, 2001
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
1
Presentation Highlights How Design Was
Developed to Meet Overall Objective
Overall Objective
Develop ARIES-AT Blanket and
Divertor Designs to Achieve High
Performance while Maintaining:
• Attractive safety features
• Simple design geometry
• Reasonable design margins as
an indication of reliability
• Credible maintenance and
fabrication processes
Design Utilizes High-Temperature
Pb-17Li as Breeder and Coolant
and SiCf/SiC Composite as
Structural Material
March 29-31, 2001
Outline
•
•
•
•
•
•
•
•
•
•
Power Cycle
Material
ARIES-AT Reactor
Coolant Routing
Blanket Design and Analysis
Divertor Design and Analysis
Fabrication
Maintenance
Manifolding Analysis
Conclusions
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
2
Brayton Cycle Offers Best Near-Term Possibility
of Power Conversion with High Efficiency*
• Maximize potential gain from high temperature
operation with SiCf/SiC
• Compatible with liquid metal blanket through
use of IHX
• High efficiency translates in lower COE and
lower heat load
Advanced Brayton Cycle Parameters Based
on Present or Near Term Technology Evolved
with Expert Input from General Atomics*
• Min. He Temp. in cycle = 35°C
• 3-stage compression with 2 inter-coolers
• Turbine efficiency = 0.93
• Compressor efficiency = 0.88
• Recuperator effectiveness = 0.96
• Cycle He fractional DP = 0.03
*R.
Schleicher, A. R. Raffray, C. P. Wong, "An Assessment of the Brayton
Cycle for High Performance Power Plant," 14th ANS Top. Meet. On TOFE
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
3
Compression Ratio is Set for Optimum Efficiency
and Reasonable IHX He Inlet Temperature
• IHX He inlet temperature
dictates Pb-17Li inlet
temperature to power core
Design Point:
• Max. cycle He temp. = 1050°C
• Total compression ratio = 3
• Cycle efficiency = 0.585
• Cycle He temp. at HX inlet = 604°C
• Pb-17 Inlet temp. to power core = 650°C
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
4
SiCf/SiC Enables High Temperature Operation and its Low
Decay Heat Helps Accommodate LOCA and LOFA Events
W/O Serious Consequences on In-Reactor Structure1,2
Properties Used for Design Analysis Consistent with Suggestions from International
Town Meeting on SiCf/SiC Held at Oak Ridge National Laboratory in Jan. 20003
•
•
•
•
•
•
•
•
•
•
•
Density
Density Factor
Young's Modulus
Poisson's ratio
Thermal Expansion Coefficient
Thermal Conductivity in Plane
Therm. Conductivity through Thickness
Maximum Allowable Combined Stress
Maximum Allowable Operating Temperature
Max. Allowable SiC/LiPb Interface Temperature
Maximum Allowable SiC Burnup
≈ 3200 kg/m3
0.95
≈ 200-300 GPa
0.16-0.18
4 ppm/°C
≈ 20 W/m-K
≈ 20 W/m-K
≈ 190 MPa
≈ 1000 °C
≈ 1000°C
≈ 3%*
1D.
Henderson, et al, and the ARIES Team, ”Activation, Decay Heat, and Waste Disposal Analyses for ARIES-AT Power Plant,"
Mogahed, et al, and the ARIES Team, ”Loss of Coolant and Loss of Flow Analyses for ARIES-AT Power Plant," 14th ANS T. M. On TOFE
3See: http://aries.ucsd.edu/PUBLIC/SiCSiC/, also A. R. Raffray, et al., “Design Material Issues for SiC /SiC-Based Fusion Power Cores,” to appear in
f
Fusion Engineering & Design, 2001
* From ARIES-I
2E.
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
5
ARIES-AT Machine and Power Parameters1,2
Power and Neutronics3 Parameters
Fusion Power
Neutron Power
Alpha Power
Current Drive Power
Overall Energy Multiplicat.
Tritium Breeding Ratio
Total Thermal Power
Ave. FW Surf. Heat Flux
Max. FW Surf. Heat
Average Wall Load
Maximum O/B Wall Load
Maximum I/B Wall Load
1719 MW
1375 MW
344 MW
25 MW
1.1
1.1
1897 MW
0.26 MW/m2
0.34 MW/m2
3.2 MW/m2
4.8 MW/m2
3.1 MW/m2
Machine Geometry
Major Radius
Minor Radius
FW Location at O/B Midplane
FW Location at Lower O/B
I/B FW Location
5.2 m
1.3 m
6.5 m
4.9 m
3.9 m
Toroidal Magnetic Field
On-axis Magnetic Field
Magnetic Field at I/B FW
Magnetic Field at O/B FW
5.9 T
7.9 T
4.7 T
1F.
Najmabadi, et al.and the ARIES Team, “Impact of Advanced Technologies on Fusion Power Plant Characteristics,” 14th ANS Top. M.on TOFE
L. Miller and the ARIES Team, “Systems Context of the ARIES-AT Conceptual Fusion Power Plant,” 14th ANS Top. Meet. On TOFE
3L. A. El-Guebaly and the ARIES Team, “Nuclear Performance Assessment for ARIES-AT Power Plant,” 14th ANS Top. Meet. On TOFE
2R.
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
6
Cross-Section and Plan View (1/6 sector) of
ARIES-AT Showing Power Core Components
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
7
Coolant Routing Through 5 Circuits
Serviced by Annular Ring Header (I)
Circuit 1: Lower Divertor + IB Blanket
LiPb Coolant
Inlet Temperature
Outlet Temperature
Blanket Inlet Pressure
Divertor Inlet Pressure
Mass Flow Rate
654°C
1100°C
1 MPa
1.8 MPa
22,700 kg/s
Circuit 1 - Lower Divertor + IB Blkt Region
Thermal Power and Mass Flow Rate:
501 MW and 6100 kg/s
Circuit 2 - Upper Divertor + 1/2 OB Blanket I
598 MW and 7270 kg/s
Circuit 3 - 1/2 OB Blanket I
450 MW and 5470 kg/s
Circuit 4 - IB Hot Shield + 1/2 OB Blanket II
182 MW and 4270 kg/s
Circuit 5 - OB Hot Shield + 1/2 OB Blanket II
140 MW and 1700 kg/s
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
8
Coolant Routing Through 5 Circuits
Serviced by Annular Ring Header (II)
Circuit 2: Upper Divertor + 1/2 OB Blanket I
March 29-31, 2001
Circuit 3: 1/2 OB Blanket I
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
9
Coolant Routing Through 5 Circuits
Serviced by Annular Ring Header (III)
Circuit 4: IB Hot Shield + 1/2 OB Blanket II
March 29-31, 2001
Circuit 5: OB Hot Shield + 1/2 OB Blanket II
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
10
ARIES-AT Blanket Utilizes a 2-Pass Coolant
Approach to Uncouple Structure Temperature from
Outlet Coolant Temperature
ARIES-AT Outboard Blanket Segment Configuration
Maintain blanket
SiCf/SiC temperature
(~1000°C) < Pb-17Li
outlet temperature
(~1100°C)
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
11
Poloidal Distribution of Surface Heat Flux
and Neutron Wall Load
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
12
Moving Coordinate Analysis to Obtain Pb-17Li
Temperature Distribution in ARIES-AT First Wall
Channel and Inner Channel
•
•
•
•
•
Assume MHD-flowlaminarization effect
Use plasma heat flux poloidal
profile
Use volumetric heat
generation poloidal and radial
profiles
Iterate for consistent
boundary conditions for heat
flux between Pb-17Li inner
channel zone and first wall
zone
Calibration with ANSYS 2-D
results
March 29-31, 2001
First Wall
Channel
vback
Pb-17Li
q''plasma
q''back
Inner
Channel
Poloidal
q'''LiPb
Radial
SiC/SiC
First Wall
vFW
Out
SiC/SiC Inner Wall
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
13
Temperature Distribution in ARIES-AT Blanket
Based on Moving Coordinate Analysis
Max. SiC/PbLi Interf.
Temp. = 994 °C
Pb-17Li Outlet
Pb-17Li Inlet
Temp. = 1100 °C
Temp. = 764 °C
• Pb-17Li Inlet Temp. = 764 °C
• Pb-17Li Outlet Temp. = 1100 °C
FW Max. CVD • From Plasma Side:
- CVD SiC Thickness = 1 mm
and SiC/SiC
- SiCf/SiC Thickness = 4 mm
Temp. =
1009°C° and
(SiCf/SiC k = 20 W/m-K)
996°C°
- Pb-17Li Channel Thick. = 4 mm
- SiC/SiC Separ. Wall Thick. = 5 mm
(SiCf/SiC k = 6 W/m-K)
• Pb-17Li Vel. in FW Channel= 4.2 m/s
• Pb-17Li Vel. in Inner Chan. = 0.1 m/s
• Plasma heat flux profile assuming no
radiation from divertor
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
14
Detailed Stress Analysis of Blanket Module to
Maintain Conservative Margins as Reliability Measure:
Stress Analysis of Outboard Module
•
•
•
6 modules per outboard segment
Side walls of all inner modules are pressure balanced except for outermodules which must be reinforced to
accommodate the Pb-17Li pressure (1 MPa)
For a 2-cm thick outer module side wall, the maximum pressure stress = 85 MPa
The side wall can be tapered radially to reduce the SiC volume fraction and benefit tritium breeding while
maintaining a uniform stress
The thermal stress at this location is small and the sum of the pressure and thermal stresses is << 190 MPa limit
•
The maximum pressure stress + thermal stress at the first wall ~60+113 MPa.
•
•
Thermal Stress
Distribution in
Toroidal Half of
Outboard Blanket
Module
(Max. s = 113 MPa)
Pressure Stress Analysis of Outer Shell of
Blanket Module (Max. s = 85 MPa)
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
15
Pressure Stress Analysis of Inner Shell Shows
Comfortable Stress Limit Margin
March 29-31, 2001
•
The inner wall is designed to
withstand the difference between
blanket inlet and outlet pressures
(~0.25 MPa).
•
The thickness of the upper and lower
wall is 5 mm.
•
The maximum stress is 116 MPa for a
side-wall thickness of 8 mm
(<<190 MPa limit)
•
In addition, the maximum pressure
differential of ~0.25 MPa occurs at
the lower poloidal location. The inner
wall thickness could be tapered down
to ~5 mm at the upper poloidal
location if needed to minimize the
SiC volume fraction.
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
16
Reference Divertor Design Utilizes
Pb-17Li as Coolant
• Single power core cooling
system
• Low pressure and
pumping power
• Analysis indicates that
proposed configuration
can accommodate a
maximum heat flux of
~5-6 MW/m2
• Alternate Options
- He-Cooled Tungsten Porous
Heat Exchanger (ARIES-ST)
- Liquid Wall (Sn-Li)
March 29-31, 2001
Outboard
Divertor Plate
Outlet Pb-17LiManifold
SiCf/SiC Poloidal Channels
Tungsten Armor
Inlet Pb-17LiManifold
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
17
ARIES-AT Divertor Configuration and
Pb-17Li Cooling Scheme
Accommodating MHD Effects:
• Minimize Interaction Parameter (<1) (Strong Inertial Effects)
• Flow in High Heat Flux Region Parallel to Magnetic Field (Toroidal)
• Minimize Flow Length and Residence Time
• Heat Transfer Analysis Based on MHD-Laminarized Flow
LiPb Poloidal Flow in ARIES-AT
Divertor Header
Example schematic illustration
of 2-toroidal-pass scheme
for divertor PFC cooling
Plasma q''
Poloidal
Direction
A
A
Cross-Section A-A
Toroidal
Direction
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
18
Temperature Distribution in Outer Divertor PFC
Channel Assuming MHD-Laminarized LiPb Flow
BT
PFC

0
0.001
0.002
0.003
0.004
0.005
1200
LiPb LiPb
1100
1100
1000
1000
900
900
800
800
Temperature (°C)
1200
700
700
600
0
0.005
0.01
Toroidal distance (m) 0.015
0.02
0.001
0.002
0.003
0.004 Radial distance (m)
0.005
0.006
Tungsten
SiC/SiC
1100
1000
900
800
700
600
• 2-D Moving Coordinate Analysis
• Inlet temperature = 653°C
• W thickness = 3 mm
• SiCf/ SiC Thickness = 0.5 mm
• Pb-17Li Channel Thickness = 2 mm
• SiCf/SiC Inner Wall Thick. = 0.5 mm
• LiPb Velocity = 0.35 m/s
• Surface Heat Flux = 5 MW/m2
Max. W Temp. = 1150°C
LiPb
Max. SiCf/ SiC Temp. = 970°C
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
19
Divertor Channel Geometry Optimized
for Acceptable Stress and Pressure Drop
•
2-cm toroidal dimension and 2.5 mm minimum
W thickness selected (+ 1mm sacrificial layer)
•
SiCf/SiC thermal + pressure stress ~ 160+30 MPa

LiPb LiPb
Pressure Stress
DP minimized to ~0.55/0.7 MPa for lower/upper
divertor
2.00
Inner Channel
Orifice
Pressure Drop (MPa)
•
PFC
BT
PFC Channel
1.50
Thermal Stress
Total
1.00
0.50
0.00
0
0.01
0.02
0.03
0.04
Toroidal Dimension of Divertor Channel (m)
March 29-31, 2001
0.05
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
20
Develop Plausible Fabrication Procedures and
Minimize Joints in High Irradiation Region
E.g. First Outboard Region Blanket Segment
1. Manufacture separate halves of the
SiCf/SiC poloidal module by SiCf weaving
and SiC Chemical Vapor Infiltration
(CVI) or polymer process;
2. Manufacture curved section of inner shell
in one piece by SiCf weaving and SiC
Chemical Vapor Infiltration (CVI) or
polymer process;
3. Slide each outer shell half over the freefloating inner shell;
4. Braze the two half outer shells together at
the midplane;
5. Insert short straight sections of inner shell
at each end;
March 29-31, 2001
Brazing
procedure
selected for
reliable
joint contact
area
Butt joint
Mortise and tenon joint
Lap joint
Tapered butt joint
Double lap joint
Tapered lap joint
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
21
ARIES-AT First Outboard Region Blanket
Segment Fabrication Procedure (cont.)
6. Form a segment by brazing six modules
together (this is a bond which is not in
contact with the coolant); and
7. Braze caps at upper end and annular
manifold connections at lower end of the
segment.
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
22
Maintenance Methods Allow for End-of-Life
Replacement of Individual Components*
• All Lifetime Components Except for:
Divertor, IB Blanket, and OB Blanket I
* L. M. Waganer, “Comparing Maintenance Approaches for Tokamak Fusion Power Plants,” 14th ANS Topical Meeting on TOFE
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
23
Manifolding Analysis
• Annular manifold
configuration with
low temperature inlet
Pb-17Li in outer
channel and high
temperature outlet
Pb-17Li in inner
channel
Pb-17Li
Inlet
q''
Pb-17Li
Outlet
ri
ro
• Can the manifold be designed to maintain
Pb-17Li /SiC Tinterface< Pb-17Li Toutlet while
maintaining reasonable DP?
• Use manifold between ring header and
outboard blanket I as example
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
24
Pb-17Li/SiC Tinterface, Pb-17Li DTBulk due to Heat Transfer in
SiCf/SiC Annular Piping, and DP as a Function of Inner
Channel Radius
• Reduction in Tinterface at the expense of additional heat transfer from outlet Pb-17Li to inlet Pb-17Li
and increase in Pb-17Li Tinlet
• Very difficult to achieve maximum Pb-17Li/SiC Tinterface < Pb-17Li Toutlet
• However, manifold flow in region with very low or no radiation
• Set manifold annular dimensions to minimize DTbulk while maintaining a reasonable DP
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
25
Typical Blanket and Divertor Parameters
for Design Point
Blanket Outboard Region 1
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
No. of Segments
No. of Modules per Segment
Module Poloidal Dimension
Avg. Module Toroidal Dimen.
FW SiC/SiC Thickness
FW CVD SiC Thickness
FW Annular Channel Thickness
Avg. LiPb Velocity in FW
FW Channel Re
FW Channel Transverse Ha
MHD Turbulent Transition Re
FW MHD Pressure Drop
Maximum SiC/SiC Temp.
Maximum CVD SiC Temp. (°C)
Max. LiPb/SiC Interface Temp.
Avg. LiPb Vel. in Inner Channel
March 29-31, 2001
Divertor
32
6
6.8 m
0.19 m
4 mm
1 mm
4 mm
4.2 m/s
3.9 x 105
4340
2.2 x 106
0.19 MPa
996°C
1009 °C
994°C
0.11 m/s
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Poloidal Dimension (Outer/Inner)
1.5/1.0 m
Divertor Channel Toroidal Pitch
2.1 cm
Divertor Channel Radial Dimension
3.2 cm
No. of Divertor Channels (Outer/Inner)
1316/1167
SiC/Si Plasma-Side Thickness
0.5 mm
W Thickness
3.5 mm
PFC Channel Thickness
2 mm
Number of Toroidal Passes
2
Outer Div. PFC Channel V (Lower/Upper)
0.35/0.42 m/s
LiPb Inlet Temperature (Outer/Inner)
653/719 °C
Pressure Drop (Lower/Upper)
0.55/0.7 MPa
Max. SiC/SiC Temp. (Lower/Upper) 970/950°C
Maximum W Temp. (Lower/Upper)
1145/1125°C
W Pressure + Thermal Stress
~30+50 MPa
SiC/SiC Pressure + Thermal Stress
~30+160 MPa
Toroidal Dimension of Inlet and Outlet Slot
1 mm
Vel. in Inlet & Outlet Slot to PFC Channel
0.9-1.8 m/s
Interaction Parameter in Inlet/Outlet Slot
0.46-0.73
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
26
Conclusions
• ARIES-AT Blanket and Divertor Design Based on High-Temperature
Pb-17Li as Breeder and Coolant and SiCf/SiC Composite as Structural
Material
–
–
–
–
–
High performance
Attractive safety features
Simple design geometry
Reasonable design margins as an indication of reliability
Credible maintenance and fabrication processes
• Key R&D Issues
– SiCf/SiC fabrication/joining, and material properties at high temperature
and under irradiation including:
• Thermal conductivity, maximum temperature (void swelling and Pb-17Li
compatibility), lifetime
– MHD effects in particular for the divertor
– Pb-17Li properties at high temperature
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
27
For More Information and Documentation
on ARIES-AT and Other ARIES Studies
Please see the ARIES web site:
http://aries.ucsd.edu/
March 29-31, 2001
A. R. Raffray, et al., ARIES-AT Blanket and Divertor, Japan-US Workshop, Tokyo
28