Page 331 - Fundamentals of Magnetic Thermonuclear Reactor Design

Blanket Chapter | 10 309

HCPB (EU): Uses the same materials as the SSTR-2 blanket, but a different
design solution. A helium-cooled FW is a separate box-like structure. Layers of
a ceramic breeder (Li SiO ) and beryllium pebbles lie in the toroidal–poloidal
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plane and alternate in the radial direction. They are helium-cooled as well.
Graphite serves as a reflector.
TAURO (EU): A silicon carbide composite is used as a structural material,
and a lead–lithium eutectic alloy acts as a tritium breeder and a coolant. The
blanket is toroidally and poloidally segmented. The coolant flows in the po-
loidal direction. The flow begins in thin FW channels and continues in several
poloidal ducts in the BZ.
ARIES-AT (United States): The concept and materials are the same as in the
previous blanket, but the design solution is somewhat different. FW channels
are a set of semi-round nested cells. LiPb flows in poloidal passes, then turns
and flows slowly as a second pass through the large inner channel.
V/Li/He (United States): The blanket uses a vanadium alloy (which offers
a potential for utilisation together with a high-temperature coolant) as a struc-
tural material, lithium, well compatible with vanadium, as a tritium breeder, and
helium as a coolant for the FW and the BZ. Tubes containing a helium coolant
are placed in a BZ that uses slowly circulating lithium. The merit of this design
is that is does not require any electrically insulating barriers. Its weakness is the
need to guard helium carefully against oxygen and hydrogen impurities, which
are harmful for vanadium.
W/Li/He (United States): In this version, the vanadium alloy is replaced with
a tungsten alloy, which allows the coolant temperature to be increased and the
corrosive effects of helium impurities to be avoided. The critical design issues
are the processes for manufacturing semi-finished products and structure ele-
ments for this blanket.
EVOLVE (United States): Similarly, this design uses a tungsten alloy as a
structural material, and lithium as both a breeder and a coolant. In this concept,
the FW and primary BZ are combined in one unit and are cooled using a lithium
evaporation cooling system. Capillary forces are employed to transport liquid
lithium to the FW. Lithium tray boiling is used for the BZ.
FFHR-2 (Japan): This design uses the V–4Cr–4Ti alloy as a structural mate-
rial and the LiF–BeF molten salt as a tritium breeder and a coolant. The FW
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and the BZ are cooled by a series of coolant passes. Behind the FW, there is a
beryllium-based multiplier, followed by the breeder and the radiation/thermal
shield (70vol.% of ferritic steel and 30vol.% of B C).
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10.5 ITER TEST BLANKET MODULES
10.5.1 Purpose and Objectives of the Test Modules

Physical and mathematical simulation, and experimental validation of the
technological systems and control instrumentation, and tests of different TBM
concepts are among the ITER’s main objectives. To this end, testing of dif-