ARIES-AT Engineering Design Parameters
Last Update: January 4, 2001
- MACHINE PARAMETERS AND OVERALL POWER BALANCE
- DESIGN LIMITS AND MATERIAL PROPERTIES
- NUCLEAR PARAMETERS
- POWER CORE OVERVIEW
- General overview
- Volumes and weights
- Surface areas
- FIRST WALL/BLANKET/REFLECTOR
- DIVERTOR
- RADIATION SHIELDING
- TF MAGNET SYSTEMS
- PF MAGNET SYSTEMS
- HEATING AND CURRENT DRIVE
- HEAT TRANSPORT AND POWER CONVERSION
- TRITIUM SYSTEMS
- BUILDINGS
1. Machine Parameters and Overall Power Balance
09/04/00 strawman (full output)
Plasma flux surfaces
x-point parameters:
Major Radius 5.2 m
Minor Radius 1.3 m
Plasma Aspect Ratio 4.0
Vertical Elongation 2.179
Triangularity 0.842
Number of Sectors 16
Fusion power 1749 MW
Neutron Power 1400 MW
Charged particle (alpha) power 349 MW
CD/heating power (MW) 34.6 MW
Charged particle+CD power 383.6 MW
Total core transport (conduction) power 267.9 MW
Bremsstrahlung power loss (MW) 55.7 MW
Core plasma line radiation (MW) MW
Core radiation fraction (brem+synchrotron+line) 0.304
Total useful thermal power (MW) 1968 MW
Gross electrical output power (MWe) 1161 MW
Net electrical output power (MWe) 1000 MW
Fusion power density 5.32 MW/m3
Plasma current (MA) 12.825
Bootstrap-current fraction 0.915
Plasma q-value 50.55
Engineering q-value 7.197
Average neutron load (MW/m2) 3.28
peak neutron load (MW/m2) 4.91
Wall load distribution table from system code
FPC mass power density (kWe/tonne) 191.3
Average mass power density (kWe/tonne) 139.6
Plant lifetime (full power years) 40
LSA=1 total COE (mill/kWeh) 52.5
2. DESIGN LIMITS, REQUIREMENTS, and MATERIAL PROPERTIES
In-vessel primary structure material SiCfSiC
low activation 3D composite
Composition
Properties
Divertor plasma-facing materials highly pure tungsten
Composition
Properties
Steel alloy for bulk shielding and structures low activation FS
Composition
Physical and mechanical properties
SiC structure radiation limit 3 yr (burnup)
FS structure radiation limit 200 dpa (18 MW-y/m2)
FS rewelding radiation limit 1.0 appm He
Temperature requiring replacement 800 °C
(due to permanent microstructure damage)
(Note: an extensive compilation of material properties for
most fusion-relevant materials is also available HERE.)
LT SC MAGNET RADIATION LIMITS
Peak fast neutron fluence to YBCO 1019 n/cm2
Peak Dose to GFF Polyimide Insulator 1011 rads
Biological Dose Limit (during operation) 2.5 mrem/hr
SAFETY LIMITS
Containment factor 104
No-evacuation limit (off-site) 1 rem (10 mSv)
Tritium inventory limit (ITER)
in-vessel 1 kg
total 4 kg
NRC clearance standards
TRITIUM BREEDING REQUIREMENT
Required breeding ratio 1.1
for fuelling plasma 1.0
calculational uncertainties (data and methods) 0.09
inventory decay, losses, supply to new machines 0.01
excess blanket capability 0.01
3. Nuclear Parameters
Overall tritium breeding ratio 1.1
6Li enrichment 90%
Overall neutron energy multiplication 1.1
(excluding VV)
Nuclear heating in VV 1% of thermal power
Detailed wall load distributions based on 3D neutronics
Nuclear Heat Loads to In-vessel Components (in MW)
(based on fusion power = 1755 MW; neutron power = 1404 MW)
| Inboard | Outboard | Divertor** | Total
|
| .
|
| FW & DP | 39 | 96 | 43# | 178 (12%)
|
| .
|
| Blanket
|
B-I (28.5 cm)| 302 | 727
| B-II (35 cm)| --- | 178
| Total | | | 1207 (76%)
| | .
| | HT shield | 40 | 9 | 112## | 161 (12%)
| | .
| | TOTAL | 381 | 1010 | 155 | 1546
| | 25% | 65% | 10% |
| | .
| | LT V.V. | 9 | 4 | 2 | 15 (<1%)
| | | |
| ** upper and lower divertor regions
|
| # 27 MW in dome, 9 MW in outer divertor plates, 7 MW in inner divertor
plates
|
| ## 58 MW in replaceable shield, 26 MW in vertical shield, 29 MW in IB
shield above/below X point
|
Radiation damage rates
peak dpa to SiC structure 57 dpa/FPY
peak He production rate 4300 appm/FPY
peak H production rate 1700 appm/FPY
SiC burnup rate 0.8 %/FPY
Component Lifetimes (in full-power years)
FW and Blanket-I 3.8 FPY
ALl other components 40 FPY
Activation results
4. Power Core Overview
GENERAL DESCRIPTION
The ARIES-AT Power Core consists of the Plasma Facing Components and Plasma
Support Systems. The primary high-temperature structural material is fiber
reinforced SiC/SiC composite. The divertor structures are
constructed from SiC/SiC with a plasma-facing coating of pure tungsten.
see power core elevation view
The power core includes components which must be replaced due to neutron
radiation damage, and components which are expected to last for the life of the
plant. Sectors are composed of the first wall, divertor plates and blanket and
are extracted as a single unit through simple radial motions on a rail system
see maintenance elevation view.
see radial build
VOLUMES and WEIGHTS:
1. Blanket/Shield/Divertor sector(1/16)
Total volumes of 1/16 sector 29.86 m3
Total weight of 1/16 sector 259.2 (103 kg)
Total drained weight of 1/16 sector 95.6 (103 kg)
Volume Density Mass
(m3) (kg/m3) (103 kg)
Blankets 17.58
SiC/SiC 4.87 3200 15.6
LiPb 12.71 9400 119.5
Shield 8.1
SiC/SiC 1.22 3200 3.9
LiPb 0.81 9400 7.6
B-FS 6.07 7800 47.4
Divertor (W coatings are not included)
1.7
SiC/SiC 0.44 3200 1.4
LiPb 0.31 9400 2.9
FS 0.95 7800 7.4
HT-Wedge 0.7
SiC/SiC 0.11 3200 0.4
LiPb 0.07 9400 0.7
B-FS 0.52 7800 4.1
Vertical Shells
W 0.78 19300 15.1
Lipb in feed ducts and manifold
LiPb 3.5 9400 32.9
2. Vacuum Vessel(1/16)
24.53
FS 12.67 7800 98.8
Water 6.6 1000 6.6
WC 5.26 15600 82.1
Total weight of 1/16 sector 187.5 (103 kg)
Surface Areas:
1. First Wall
Inboard 110.9 m2
Outboard 243.5 m2
Total 354.4 m2
2. Divertor
Inboard 40.9 m2
Dome 50.8 m2
Outboard 54.9 m2
Total 146.6 m2
5. First Wall and Blanket
SiC composite joint design options
SiC/SiC Properties
GENERAL DESCRIPTION
For waste minimization and cost saving reasons, the blanket is subdivided
radially into two zones (see elevation view of sector):
a replaceable first zone in the inboard and outboard, and a life of plant
second zone in the outboard (see plan view of the power core sector).
Each of the 16 sectors comprises one inboard blanket segment, two replaceable
outboard segments, and two life-of-plant outboard segments.
The design is modular - each segment consisting of 6 modules
(see outboard cross section and first outboard unit cell).
It consists of a simple annular box through which the Pb-17Li flows in two
poloidal passes. Positioning ribs are attached to the inner annular wall
forming a free floating assembly inside the outer wall. These ribs divide the
annular region into a number of channels through which the coolant first flows
at high-velocity to keep the outer walls cooled. The coolant then turns and
flows very slowly as a second pass through the large inner channel from which
the Pb-17Li exits at high temperature. This flow scheme enables operating
Pb-17Li at a high outlet temperature (1100°C) while maintaining the blanket
SiCf/SiC composite and SiC/PbLi interface at a lower temperature (~1000°C).
The first wall consists of a 4-mm SiCf/SiC structural wall on top of which is
deposited a 1-mm CVD SiC armor layer.
o/b MATERIALS
First wall coolant Pb83Li17
Breeder Pb-17Li, 60% enriched 6Li
Plasma facing material coating none
First wall structure SiC/SiC composite
Blanket structure SiC/SiC composite
Structure lifetime 3 FPY (3% burnup)
o/b GEOMETRY METRICS
Number of sectors 16
Number of segments 32
Number of modules per outboard segment 6
Module poloidal height 6.8 m
Average module toroidal width 0.19 m
Outboard FW radius at midplane 6.5 m
Outboard FW Location at Lower/Upper End 4.9 m
Inboard FW Location 3.9 m
Magnetic Field at Inboard FW 7.9 T
Magnetic Field at Outboard FW 4.7 T
Total FW area (excluding divertor surfaces) 355 m2
outboard 244 m2
inboard 111 m2
First structural wall thickness 5 mm
SiC composite 4 mm
CVD coating 1 mm
First coolant channel depth 4 mm
Inner wall thickness 5 cm
W stabilizing shell thickness 5 cm
W operating temperature 1100 °C
Total thickness of inboard region 30 cm
Total thickness of first outboard region 30 cm
Total thickness of second outboard region 35-45 cm
Power Flows and Neutronics
Average first wall heat flux 0.26 MW/m2
Peak first wall heat flux 0.34 MW/m2
Average neutron wall load 3.2 MW/m2
Peak neutron wall load
outboard 4.8 MW/m2
inboard 3.1 MW/m2
Heat generation in FW Pb-17Li per MW/m2 of wall load 3.75 MW/m2
Heat generation in FW SiC per MW/m2 of wall load 5.0 MW/m2
Total Thermal Power in Blanket
First Inboard Region 354 MW
First Outboard Region 901 MW
Second Outboard Region 142 MW
THERMAL HYDRAULICS
Coolant Pb-17Li
Coolant inlet pressure 1 MPa
Blanket Pressure Drop 0.25 MPa
Total mass flow 22,700 kg/s
Mass flow per outboard segment 76 kg/s
Flow velocity, first wall (average) 4.2 m/s
FW Re 3.9 x 105
FW transverse Ha number 4340
Transition to turbulence Re 2.2 x 106
FW MHD pressure drop 0.19 MPa
Flow velocity, blanket (average) 0.11 m/s
Coolant inlet temperature
to in-reactor components 654 °C
to inboard blanket region 785 °C
to first outboard blanket region 764 °C
Blanket outlet temperature 1100 °C
Maximum SiC/SiC temperature 996 °C
Maximum CVD SiC temperature 1009 °C
Maximum PbLi/SiC interface temperature 994 °C
Net thermal efficiency 59%
MANIFOLDS and COOLANT ROUTING
Manifolds and pipes carry coolant from in-vessel components to the heat
exchangers. They may serve additional functions to assist in shielding
and to provide structural support.
To simplify the cooling system and minimize the number of coolants, the Pb-17Li
is used to cool the blanket as well as the divertor and hot shield regions.
The coolant is fed through an annular ring header surrounding the power core
(see figure) from which it is routed to each of 16 reactor sectors through
the following five subcircuits:
- Series flow through the lower divertor and inboard blanket region
(total thermal power and mass flow rate = 501 MW and 6100 kg/s), see
figure.
Total Thermal Power 501 MW
Mass Flow Rate 6100 kg/s
Inlet and outlet temperature 653 °C, 1100°C
In-Reactor Inlet Pressure 1 MPa
In-Reactor Pressure Drop 0.79 MPa
In-Reactor Pumping Power 3.3 MW
- Series flow through the upper divertor and one segment of the first outer
blanket region (598 MW and 7270 kg/s), see figure
Total Thermal Power 598 MW
Mass Flow Rate 7270 kg/s
Inlet and outlet temperature 653°C, 1100°C
In-Reactor Inlet Pressure 1 MPa
In-Reactor Pressure Drop 0.74 MPa
In-Reactor Pumping Power 3.3 MW
- Flow through the second segment of the first outer blanket region (450 MW
and 5470 kg/s), see figure
Total Thermal Power 450 MW
Mass Flow Rate 5470 kg/s
Inlet and outlet temperature 653°C, 1100°C
- Series flow through the inboard hot shield region and first segment of the
second outer blanket region (182 MW and 4270 kg/s), see figure
Total Thermal Power 182 MW
Mass Flow Rate 2210 kg/s
Inlet and outlet temperature 653°C, 1100°C
- Series flow through the outboard hot shield region and second segment of
the second outer blanket region (140 MW and 1700 kg/s), see figure
Total Thermal Power 140 MW
Mass Flow Rate 1700 kg/s
Inlet and outlet temperature 653°C, 1100°C
Fabrication
As a reliability measure, minimization of the number and length of brazes was a
major factor in evolving the fabrication procedure for the blanket. The
proposed fabrication scheme requires three radial/toroidal coolant-containment
brazes per module, as illustrated by the following fabrication steps for an
outboard segment consisting of 6 modules:
- Manufacturing separate halves of the SiCf/SiC poloidal module by SiCf weaving
and SiC Chemical Vapor Infiltration (CVI) or polymer process;
- Inserting the free-floating inner separation wall in each half module;
- Brazing the two half modules together at the midplane;
- Brazing the module end cap;
- Forming a segment by brazing six modules together (this is a joint which is
not in contact with the coolant); and
- Brazing the annular manifold connections to one end of the segment.
Figures:
6. Divertor
GENERAL DESCRIPTION
The plasma uses a symmetric double-null configuration with divertors.
The flux surfaces have a separatrix at top and bottom.
To simplify the cooling system and minimize the number of coolants, the blanket
Pb-17Li is also used to cool the divertor. Pb-17Li as coolant has a relatively
low thermal conductivity and tends to offer limited heat removal performance in
particular in the presence of a magnetic field. In order to accommodate MHD
effects, the proposed divertor design:
- Minimizes the interaction parameter (<1) which represents the ratio of MHD
to inertial forces;
- Directs the flow in the high heat flux region parallel to the toroidal
magnetic field; and
- Minimizes the Pb-17Li flow path and residence time in the high heat flux
region.
As shown in these figures
outboard plate,
cooling channel cross section
the divertor plate design consists of a number of 2-cm x 2.5-cm SiCf/SiC
poloidal channels. The front SiCf/SiC wall is very thin (0.5 mm) in order to
maintain the maximum temperature and combined stress limits to <1000°C, and
<190 MPa, respectively. A 3.5-mm plasma facing layer of W is bonded to the thin
SiCf/SiC to provide additional structure to accommodate the 1.8-MPa
Pb-17Li pressure and to provide sacrificial armor (~1 mm). In each channel a
T-shaped flow separator is inserted. The Pb-17Li flows poloidally through one
half of the channel which acts as an inlet header. The flow is then forced to
the PFC region through small holes at one side of the channel. The flow through
these small holes is inertial with an interaction parameter <1. The Pb-17Li
then flows toroidally to cool the high heat flux region through a very short
flow path (2 cm). It is then routed back to the other side of the poloidal
channel serving as outlet header. The Pb-17Li velocity through the toroidal PFC
channel can be adjusted by changing the dimension of this channel or by
increasing the number of toroidal passes through a plate. The reference design
uses a 2-mm channel and 2-pass flow resulting in a 0.35 m/s velocity in the
toroidal channel and a 0.06 s residence time.
The resulting Pb-17Li pressure drop through the divertor based on the proposed
flow configuration is estimated at about 0.7 MPa. This is significantly larger
than the blanket pressure drop. To minimize pressure stresses in the piping and
blanket system, the Pb-17Li in the inlet manifold is kept at 1.1 MPa. The
Pb-17Li is then pressurized to 1.8 MPa just before flowing though the divertor
by means of an E-M pump making use of the existing toroidal magnetic field. The
outlet flow from the divertor then rejoins the blanket inlet manifold at about
1.1 MPa.
MATERIALS
Coolant Pb-17Li
Divertor strucutral material SiCf/SiC
Plasma facing armor material W
Manifolds and support structures SiCf/SiC
GEOMETRY METRICS
Divertor Plate Poloidal Dimension (Outer/Inner) 1.5/1.0 m
Divertor Channel Toroidal Pitch 2.1 cm
Divertor Channel Radial Dimension 3.2 cm
Number of Divertor Channels (Outer/Inner) 1316/1167
Total Number of Divertor Channels (Upper+Lower) 4967
SiCf/SiC Plasma-Side Thickness 0.5 mm
W Thickness 3.5 mm
PFC Channel Thickness 2 mm
Number of Toroidal Passes 2
Toroidal Dimension of Inlet and Outlet Feeder Slots 1 mm
Inboard Divertor Plate Area 40.9 m2
Outboard Divertor Plate Area 54.9 m2
Divertor Dome Area 50.8 m2
Total Divertor Area 146.6 m2
Toroidal Magnetic Field at Divertor (Outer/Inner) 7/7.9 Tesla
TRANSPORT POWER INVENTORY
Total Transport Power (alphas plus CD power) 256 MW
Total Thermal Power to Divertor (transport + neutron) 296 MW
Thermal Power to Upper or Lower Divertor 148 MW
Average Divertor Heat Flux 1.75 MW/m2
Peak Divertor Heat Flux (in analogy with ARIES-RS analysis) 5.0 MW/m2
THERMAL HYDRAULICS
Pb-17Li Mass Flow Rate (Lower/Upper) 6100/7270 kg/s
Velocity in Lower Divertor PFC Channel (Outer/Inner) 0.35/0.6 m/s
Velocity in Upper Divertor PFC Channel (Outer/Inner) 0.42/0.71 m/s
Velocity in Inlet & Outlet Slot to PFC Channel 0.9-1.8 m/s
Interaction Parameter in Inlet/Outlet Slot 0.46-0.73
Pb-17Li Inlet Temperature (Outer/Inner) 653/719 °C
Pressure Drop (Lower/Upper) 0.55/0.7 MPa
Maximum SiCf/SiC Temperature (Lower/Upper) 970/950 °C
Maximum W Temperature (Lower/Upper) 1145/1125 °C
W Pressure + Thermal Stress ~35+50 MPa
SiCf/SiC Pressure + Thermal Stress ~35+160 MPa
PROPERTIES USED IN T/H ANALYSIS:
PbLi
W
SiC/SiC
FABRICATION
The divertor fabrication scheme aims at minimizing brazing and can be
summarized in the following sequence of steps:
- Manufacture separate SiCf/SiC toroidal halves of the divertor
plate by SiCf weaving and SiC CVI or polymer process; maintain
constant channel toroidal dimensions but tapered side wall thicknesses to
account for torus geometry;
- Insert the inner SiCf/SiC separation wall in each divertor channel;
- Braze the two toroidal halves of the divertor plate together;
- Braze the end cap and manifold on each end; and
- Bond the W layer to the SiCf/SiC front wall by plasma spray.
Figures:
- Partial tungsten layer of the outboard divertor plate
- Partial SiC/SiC ducts of the outboard divertor plate
- Partial outboard divertor ducts with inserted coolant guides
- Partial outboard divertor ducts with inserted coolant guides
- Partial outboard divertor plate with brazed coolant manifolds
7. Radiation Shielding
GENERAL DESCRIPTION
All three primary in-vessel components (blanket, shield and vacuum vessel)
provide a shielding function. The magnet shielding consists of three
elements: the inboard, outboard and divertor shields. All shields employ SiC
structure and operate at high temperature (~700°C) and are cooled with
PbLi.
MATERIALS
Coolant Pb-17Li
Shield structure SiC/SiC
Filler borated ferritic steel (composition)
Structure lifetime 40 FPY
GEOMETRY METRICS
Inboard shield thickness 24 cm
Outboard shield thickness 15 cm
Divertor shield thickness 30 cm
SiC fraction 15 %
PbLi fraction 10 %
B-FS fraction 75 %
Maintenance gap between shield and CP 2 cm
W stabilizing shell thickness 4 cm
W operating temperature 1100 °C
Biological shield
The biological shield is located outside the cryostat boundary.
The shield provides long-term protection to plant workers during
operation. Access to power core components is provided through
passage doors.
Thickness 2.6 m
Materials Steel-reinforced concrete
Volumetric heating < 0.1 MW
Component lifetime Life of Plant
Coolant No active coolant
8. Toroidal Field Magnet System
GENERAL DESCRIPTION
NO INFORMATION PROVIDED
9. Poloidal Field Magnet System
GENERAL DESCRIPTION
NO INFORMATION PROVIDED
10. HEATING AND CURRENT DRIVE
General Description:
There are two radiofrequency (rf) systems for heating and current drive:
1. Ion-cyclotron-resonance-frequency (ICRF) fast wave,
2. lower hybrid wave (LHW) subsystems.
Power is delivered to the plasma via rf launchers which are in turn fed by
transmission lines. The rf in-vessel components are made of
tungsten-coated silicon carbide composite and actively cooled by PbLi.
Subsystem ICRF LHW
Frequency (GHz) 0.096 2.5 - 3.6
Wall-Plug-to Plasma Efficiency 0.75 0.46
Wall-Plug Power (MW) 20.0 105.9
Power Delivered to Plasma (MW) 15.0(1) 48.7(2)
Current-Drive Power (MW) 3.3 34.1
Total Current Drive Power 37.4 MW
Current-Drive Efficiency 0.031 A/W
Normalized Efficiency 3.82 x 1020 A/m2-W
Total First-Wall Penetration 2.06 m2
Total First-Eall Area 425.6 m2
Driven Current 1.15 MA
Current Drive Efficiency 0.031 A/W
(1) This is power delivered during startup phase.
(2) This is current drive power divided by launcher directivity (=0.7).
A. ICRF SUBSYSTEM
(A1) LAUNCHER:
The entire ICRF launcher system is composed of one launcher unit that
consists of a toroidal array of 4 folded-waveguide elements.
The basic element of the array is a folded-rectangular-waveguide
quarter-wavelength resonant cavity fed by a coaxial transmission line
(coax) at the backplate. [(see figure showing cavity)] The front aperture
is covered by a polarizer plate that covers alternate fold apertures, and
is slightly recessed from the first wall. [(see figure showing the front
plate)] A transverse ridge structure, or capacitive diaphragm, is inserted
at the back end of each fold to function as an impedance transformer that
effectively reduces the cavity radial thickness. [(see figure showing the
diaphragm)]
LAUNCHER GEOMETRY METRICS
System Toroidal Width 1.56 m
System Poloidal Height 0.51 m
System Radial Thickness 0.92 m
System First-Wall Area 0.80 m2
Location Outboard midplane
System Volume 0.73 m3
Cavity Toroidal Width 0.39 m
Cavity Poloidal Height 0.51 m
Cavity Radial Thickness 0.92 m
Cavity Wall Thickness 0.01 m
Number of Folds 10
Fold Gap Width 0.04 m
Number of Vanes 9
Vane Thickness 0.01 m
Vane Radial Depth 0.62 m
Diaphragm Radial Thickness 0.14 m
Diaphram Poloidal Height 0.02 m
Thickness of Coupling Region 0.35 m
LAUNCHER MATERIALS:
Cavity Walls and Vanes SiC composite coated with W
Coating Thickness 0.064 mm
Coolant PbLi
Coolant Duct Diameter 0.6 cm
Coolant Temperature 1000 °C
(A2) TRANSMISSION LINE:
The coax is used as the base unit for power transmission and coupling to
the launcher system. The inner conductor forms a loop with the cavity
sidewall inside the coupling region, and is supported outside the shielding
region by BeO vacuum windows. Outside the vacuum window the coax is
pressurized with SF6.
TRANSMISSION LINE GEOMETRY METRICS
Outer Diameter 15.6 cm
Inner Diameter 7.10 cm
Characteristic Impedance 50 ohms
Volume (for 1.5 m length) 0.346 m3
TRANSMISSION LINE MATERIALS:
Inner and Outer Cylinders SiC composite Coated with W
Coating Thickness 0.064 mm
Coolant PbLi @ 1000 °C
Vacuum Window BeO
B. LHW SUBSYSTEM
(B1) LHW LAUNCHER:
The entire LHW launcher system is composed of five separate modules which are
designed to radiate different wave spectra. Each module consists of a toroidal
array of alternate passive and active (p/a) TE50 rectangular waveguides with
the short (long) dimension in the toroidal (poloidal) direction. The basic
element of the launcher unit is the passive-active multijunction (PAM) grill
modeled after the ITER-EDA design. Each PAM grill is driven by a number of
TE10 - TE50 mode converters with a projected conversion efficiency of 98%.
LHW LAUNCHER GEOMETRY METRICS
unit 1 unit 2 unit 3 unit 4 unit 5
Wavelength (cm) 4.72 3.84 3.08 2.20 2.40
Frequency (GHz) 3.6 3.6 3.6 3.6 2.5
Directivity 0.7 0.7 0.7 0.7 0.7
Delivered power (MW) 4.0 6.0 11.4 12.0 17.1
Array size (row x # of p/a wg's) 1x16 2x16 2x32 2x48 2x48
Toroidal width (m) 0.50 0.36 0.66 0.71 0.70
Poloidal height (m) 0.20 0.40 0.40 0.40 0.60
First-Wall Area (m2) 0.10 0.16 0.26 0.28 0.46
Waveguide (p/a) toroidal width (cm) 3.14 2.56 2.06 1.46 1.60
Waveguide (p/a) poloidal height (cm) 20 20 20 20 30
Location Approximately 1 meter below outboard midplane
LHW LAUNCHER MATERIALS:
Waveguide walls SiC composite coated with W
Coating thickness 0.015 mm
Coolant PbLi @ 1000 °C
(B2) TRANSMISSION LINE:
The basic element is the circular waveguide.
Diameter of waveguide is 4.8 cm and 7.3 cm for 3.6 GHz and 2.5 GHz,
respectively.
TRANSMISSION LINE MATERIALS:
Same as in ICRF launcher.
11. Heat Transport and Power Conversion
GENERAL DESCRIPTION
The Brayton cycle offers the best near-term possibility of power conversion
with high efficiency and is chosen to maximize the potential gain from high
temperature (1100°C) operation of the Pb-17Li which after exiting the
blanket is routed through a heat exchanger with the cycle He as secondary
fluid. The Brayton cycle considered (see figure)
includes three-stage compression with two intercoolers and a high efficiency
recuperator. Its main parameters are set under the assumption of state of the
art components and/or with modest and reasonable extrapolation
PARAMETERS
He fractional pressure drop (ex-vessel) 0.025
He pressure 15-20 MPa
Lowest He temperature in the cycle (heat sink) 35 °C
Turbine efficiency 93 %
Compressor efficiency 90 %
Recuperator effectiveness 96 %
Maximum He cycle temperature 1050 °C
Cycle efficiency 58.5 %
12. Trtitium Systems
Total coolant flow rate 2.36E+4 kg/s
Coolant flow rate to tritium recovery process 2.36E+3 kg/s
Tritium partial pressure over LiPb 20 Pa
Tritium partial pressure in the He purge 2 Pa
Tritium recovery system temperature 1090 °C
Tritium recovery rate 300 g/d
He purge flow rate 2.3 m3/s
Tritium concentration in LiPb 1.6 wppb
Tritium inventory in LiPb 10 g
Tritium inventory in SiC 300 g
Net plant release rate <10 Ci/d
Polonium and Mercury Control
Since the Po concentration increase per coolant pass is much lower than the
allowable Po concentration, the required Po clean up efficiency is very low.
Po can either be removed from the tritium recovery system, or a vacuum
distillation system.
Based on the experimental data, the Po evaporation rate in He is about six
order of magnitude lower than the calculated rate. Even with this low
evaporation rate, the Po can be removed from the tritium recovery system.
Hg (yet to be assessed) probably can also be removed in the tritium recovery
system. Both Po and Hg can be separated from the tritium purge gas by a cold
trap.
13. Buildings
Plan View of maintenance level
North-south section view of power core building
East-west section view of power core building
CONTRIBUTORS:
System parameters Mark Tillack/Ron Miller
Nuclear parameters Laila El-Guebaly
Radial build, materials Laila El-Guebaly
Blanket and divertor Rene Raffray/Xueren Wang
Shield Laila El-Guebaly
Power conversion Rene Raffray
rf H&CD T.K. Mau
Tritium systems Dai Kai Sze
Magnets Leslie Bromberg
Buildings Xueren Wang