Overview of Chamber Blanket Study

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Overview of Chamber Blanket Study

• Presented by A. René Raffray
• UCSD
• With contributions from M. Sawan(UW), I.
  Sviatoslavsky(UW) and X. Wang
• HAPL Meeting
• PPPL
• Princeton, NJ
• October 27-28, 2004

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What Does a Blanket Do and How Does It Interface
with Other Components?
Vacuum vessel additional neutron shielding
Blanket (contains lithium) Uses Li n
reaction to breed tritium - Need enough
breeding for tritium self-sufficiency
(TBRgt1.1) - Requirement on thickness of
blanket (30-90 cm) - Impact on pumping duct
length - Requirement on coverage (90 or
more) - Impact on surface area required for
penetrations (laser, target, pumping
ducts) - Provides some neutron shielding
function also Transfer energy deposition to
coolant to drive power cycle for efficient
electricity production - Choice of coolant
affected by other components - e.g. liquid
metal coolant possibly impacted by use of
magnetic deflection of ions to protect final
optics (MHD effects) - Level of inlet
outlet coolant temperatures required for
acceptable efficiency impact lifetime of armor
and, indirectly, yield, size of chamber or
the necessity to have a protective gas in the
chamber Maintenance requirements affect layout
of power plant and is impacted by layout of
other components
Blanket coolant
Armor Accommodate X-rays ions energy
deposition (10-100 mm)
Power cycle
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Goal is to Develop At Least One Credible
IFE-Specific Blanket Concept Compatible with
theCchoice of Armor (W) and Structural Material
(FS)
Strategy Make the most of information from MFE
blanket/FW effort. Phase I Scoping
study - Several (2-4) blanket concepts will be
developed to the point where we can
intelligently evaluate then in terms of key
issues, including - Performance, reliability,
simplicity, safety and perception from the
outside - Down-selection to one (or perhaps 2)
preferred option(s) for more detailed study
during Phase II Phase II Detailed design
analysis - One (or perhaps 2) preferred
option(s) selected from Phase I - Cover all
key aspects to end up with a strongly- credibl
e and attractive integrated design. - fabricatio
n, operation, maintenance and integration Chambe
r configuration needs to be considered in an
integrated system context to show that this
can lead to a credible and attractive laser
IFE power plant. Close coordination with
first wall/armor effort, Materials Working
Group and system studies
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Several Possible Blanket Concepts from MFE

• Resources and time only allow for consideration
  of 3(or 4) concepts during Phase I
• Some concerns with using water as chamber
  coolant
• - Potential safety issues with Pb-17Li and/or Li
  as breeding material and Be as multiplier
• - Corrosion issues
• - High pressure
• For Phase I, focus on He as coolant and/or
  self-cooled blanket concepts
• - Self-cooled Li
• - He-cooled ceramic-breeder
• - He-cooled or dual cooled Pb-17Li
• - Dual or He-cooled molten salt (if possible, but
  requires more RD and is lower priority)
• Above concepts cover a good range of
  performance and RD needs
• - Maximize performance
• Choose optimum power cycle for conditions
  Brayton or Rankine cycle (e.g. performance,
  impact on accidental scenario of using steam
  in Rankine cycle)
• Maximize cycle efficiency for given material
  constraints
• - Design simplicity as a measure of reliability
• Minimize welds, channels, joints and coolant
  pressure (if possible)

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