Field-Reversed Configuration Fusion Power Plants

Field-Reversed Configuration Field-Reversed Configuration Fusion Power PlantsFusion Power Plants

John F. SantariusJohn F. SantariusUniversity of WisconsinUniversity of Wisconsin

Workshop on Status and Promising Workshop on Status and Promising Directions for FRC ResearchDirections for FRC Research

PPPLPPPLJune 8-9, 1999June 8-9, 1999

JFS 1999 University of Wisconsin

CollaboratorsCollaborators

University of WisconsinUniversity of Wisconsin Canh NguyenCanh Nguyen Laila El-GuebalyLaila El-Guebaly Gil EmmertGil Emmert Doug HendersonDoug Henderson Hesham KhaterHesham Khater Jerry KulcinskiJerry Kulcinski Elsayed MogahedElsayed Mogahed Sergei RyzhkovSergei Ryzhkov Mohamed SawanMohamed Sawan

University of WashingtonUniversity of Washington Loren SteinhauerLoren Steinhauer

University of IllinoisUniversity of Illinois George MileyGeorge Miley


FRC Power Plant ApplicationsFRC Power Plant Applications

D-3HeD-T

Solid walls

Commercialelectricityproduction

Proliferation-resistantelectricity

Spacepropulsion

Liquid walls

Otherapplications?

Hydrogenproduction?

Destructionof waste?

Field-Reversed Mirror (D-T, Condit, et al., LLNL, 1976)Field-Reversed Mirror (D-T, Condit, et al., LLNL, 1976)

University of Wisconsin JFS 1999


SAFFIRE Field-Reversed MirrorSAFFIRE Field-Reversed Mirror(D-(D-33He, Miley, et al., Univ. of Illinois, 1978)He, Miley, et al., Univ. of Illinois, 1978)


ARTEMIS Field-Reversed ConfigurationARTEMIS Field-Reversed Configuration(D-(D-33He, Momota, et al., NIFS, 1992)He, Momota, et al., NIFS, 1992)


A D-T FRC Engineering Scoping StudyA D-T FRC Engineering Scoping StudyIs In ProgressIs In Progress

Collaboration of Universities of Wisconsin, Washington, and Collaboration of Universities of Wisconsin, Washington, and Illinois.Illinois.

Objective: To investigate critical engineering issues for D-T Objective: To investigate critical engineering issues for D-T FRC Power Plants.FRC Power Plants. Systems analysisSystems analysis Tritium-breeding blanket designTritium-breeding blanket design Radiation shielding and damageRadiation shielding and damage Activation, safety, and environmentActivation, safety, and environment Plasma modelingPlasma modeling Current driveCurrent drive Plasma-surface interactionsPlasma-surface interactions


FRC Plasma Power Flows Differ FRC Plasma Power Flows Differ Significantly from Tokamak Power FlowsSignificantly from Tokamak Power Flows

Power density can be very high due to its Power density can be very high due to its 22BB44 scaling, but this does not necessarily imply an scaling, but this does not necessarily imply an unmanageable first-wall heat flux.unmanageable first-wall heat flux.

Charged-particle power transports from internal plasmoid to edge region and then out ends of Charged-particle power transports from internal plasmoid to edge region and then out ends of fusion core.fusion core.

Expanded flux tube in end chamber reduces heat and particle fluxes, so charged-particle transport Expanded flux tube in end chamber reduces heat and particle fluxes, so charged-particle transport power only slightly impacts the first wall.power only slightly impacts the first wall.

Mainly bremsstrahlung power contributes to first-wall surface heat.Mainly bremsstrahlung power contributes to first-wall surface heat. Relatively small peaking factor along axis for bremsstrahlung and neutrons.Relatively small peaking factor along axis for bremsstrahlung and neutrons.

Not to scaleExpandedflux tube toreduceheat flux

FRC core region

Charged particlesBremsstrahlungNeutrons

Linear Geometry Greatly Facilitates EngineeringLinear Geometry Greatly Facilitates Engineering

Flow of charged particles to end plate reduces first-wall Flow of charged particles to end plate reduces first-wall surface heat flux.surface heat flux.

Modules containing blanket, shield, and magnet can be Modules containing blanket, shield, and magnet can be replaced as single units due to their moderate mass.replaced as single units due to their moderate mass.

Maintenance should be easier and improve reliability and Maintenance should be easier and improve reliability and availability.availability.

Considerable flexibility exists for placement of pipes, Considerable flexibility exists for placement of pipes, manifolds, etc.manifolds, etc.

Direct conversion of transport power to electricity could Direct conversion of transport power to electricity could increase net efficiency.increase net efficiency.

University of Wisconsin JFS 1999


FRC Geometry Greatly Reduces the FRC Geometry Greatly Reduces the ‘Divertor’ Problem‘Divertor’ Problem

MHD tilt instability, probably the closest FRC analogue MHD tilt instability, probably the closest FRC analogue to a tokamak disruption, will send the plasma along the to a tokamak disruption, will send the plasma along the axis and into the end chamber, where measures can be axis and into the end chamber, where measures can be more easily taken to mitigate and localize the effects.more easily taken to mitigate and localize the effects.

Steady-state heat flux is broadly spread and due almost Steady-state heat flux is broadly spread and due almost exclusively to bremsstrahlung radiation power.exclusively to bremsstrahlung radiation power.

Edge region vacuum pumps well and should shield the Edge region vacuum pumps well and should shield the core plasma from most impurities..core plasma from most impurities..


Compact Toroids Might Provide both Compact Toroids Might Provide both Fueling and Current Drive for FRC’sFueling and Current Drive for FRC’s

Compact toroids carry particles and current at 100’s of Compact toroids carry particles and current at 100’s of km/s.km/s.

Small spheromaks merging with a large FRC will relax to Small spheromaks merging with a large FRC will relax to an FRC with a slightly larger current.an FRC with a slightly larger current.

Added helicity must balance resistive decay of the plasma Added helicity must balance resistive decay of the plasma current.current.

Added particles should balance particle transport losses.Added particles should balance particle transport losses. Spheromaks would be injected at ~1 Hz.Spheromaks would be injected at ~1 Hz. Either vertical or horizontal geometry should work.Either vertical or horizontal geometry should work. Key question is power required for self-consistent fueling Key question is power required for self-consistent fueling

and current drive.and current drive.


D-T FRC Engineering Scoping StudyD-T FRC Engineering Scoping StudyKey AssumptionsKey Assumptions

Rotating magnetic field (RMF) current drive.Rotating magnetic field (RMF) current drive. Steady-state operation.Steady-state operation. He/LiHe/Li220/SiC for coolant/breeder/structure of first wall and 0/SiC for coolant/breeder/structure of first wall and

blanket.blanket. Superconducting magnets, possibly high-Tc.Superconducting magnets, possibly high-Tc. Thermal energy conversion only.Thermal energy conversion only. Horizontal (radial) maintenance of blanket/shield/magnet Horizontal (radial) maintenance of blanket/shield/magnet

modules (~5 m length).modules (~5 m length). ARIES economic model assumptions.ARIES economic model assumptions.


Liquid-Walled FRC Power Plants Might Liquid-Walled FRC Power Plants Might Achieve Extremely High Power DensitiesAchieve Extremely High Power Densities

The APEX study uses the FRC as a key alternate to the The APEX study uses the FRC as a key alternate to the tokamak.tokamak.

Thick liquid walls (Li, Flibe, LiPb, LiSn) would Thick liquid walls (Li, Flibe, LiPb, LiSn) would attenuate neutrons and serve asattenuate neutrons and serve as Tritium breederTritium breeder Radiation shieldRadiation shield Heat transfer mediumHeat transfer medium

spheromak forfueling and

current drivecore plasma

edge plasmaliquid wall

solid shieldmagnet

Not to scale


FRC Magnets Fit Well withinFRC Magnets Fit Well within Superconducting State-of-the-Art Superconducting State-of-the-Art

Magnetic fields for both D-T and D-Magnetic fields for both D-T and D-33He FRC power-plant coils He FRC power-plant coils are usually projected to be <6 T.are usually projected to be <6 T.

Externally generated field within fusion core nearly equals the Externally generated field within fusion core nearly equals the field on the coils field on the coils increased power density (B increased power density (B44).).

MHD pressure drop for liquid-metal coolants will require less MHD pressure drop for liquid-metal coolants will require less pumping power than in tokamaks.pumping power than in tokamaks.

High-temperature superconductors presently operate at relevant High-temperature superconductors presently operate at relevant current densities at 5 T in short lengths.current densities at 5 T in short lengths.

High-temperature superconductors should be more resistant to High-temperature superconductors should be more resistant to quenching and may, therefore, reduce the required radiation quenching and may, therefore, reduce the required radiation shield.shield.


Pulsed FRC Power PlantsPulsed FRC Power Plants High FRC power density gives flexibility that would help High FRC power density gives flexibility that would help

accommodate changes necessitated by pulsing.accommodate changes necessitated by pulsing. High-temperature superconductors would facilitate a pulsed High-temperature superconductors would facilitate a pulsed

design.design. Neutron-fluence limited, therefore unaffected by Neutron-fluence limited, therefore unaffected by

pulsing, rather than heat-flux limited.pulsing, rather than heat-flux limited. More robust against quenching due to pulsed fields.More robust against quenching due to pulsed fields.

Might be fueled by periodic CT injection for fueling and Might be fueled by periodic CT injection for fueling and current drive.current drive. Also potentially for inducing instability for ash removal Also potentially for inducing instability for ash removal

and plasma MHD conversion?and plasma MHD conversion? Transport implications?Transport implications?


D-3He Fuel Could Make Good Use of theD-3He Fuel Could Make Good Use of theHigh Power Density Capability of FRC’sHigh Power Density Capability of FRC’s

D-T fueled innovative concepts become limited by first-D-T fueled innovative concepts become limited by first-wall neutron or surface heat loads well before they reach wall neutron or surface heat loads well before they reach or B-field limits. or B-field limits.

D-T fueled FRC’s optimize at B D-T fueled FRC’s optimize at B 3 T. 3 T.

D-3He needs a factor of ~80 above D-T fusion power D-3He needs a factor of ~80 above D-T fusion power densities.densities. Fusion power density scales as Fusion power density scales as 22BB44.. Superconducting magnets can reach at least 20 T.Superconducting magnets can reach at least 20 T. Potential power-density improvement by increasing Potential power-density improvement by increasing

B-field to limits is (20/3)^4 ~ 2000 !B-field to limits is (20/3)^4 ~ 2000 !


Proliferation-Resistant FRC Power PlantProliferation-Resistant FRC Power PlantMay Be Possible (Probably Requires D-May Be Possible (Probably Requires D-33He)He)

Minimal radiationshield to reduce

space for D-Tshielding

Superconducting,high-field magnet

for high fusionpower density

Small plasmato reduce

space for D-Tshielding

Organic coolant tomake high-flux D-Toperation difficult.

High- for high fusionpower density

Direct converterfor increasedelectric powerper unit fusion

power


ConclusionsConclusions

From a fusion energy development perspective, From a fusion energy development perspective, FRC’s occupy the important position of leading the FRC’s occupy the important position of leading the -driven, engineering-attractiveness route.-driven, engineering-attractiveness route.

The cylindrical geometry and disruption-free The cylindrical geometry and disruption-free operation of D-T FRC’s should allow them to operation of D-T FRC’s should allow them to overcome the major engineering obstacles facing overcome the major engineering obstacles facing D-T tokamaks.D-T tokamaks.

FRC’s match D-FRC’s match D-33He fuel well, and the combination He fuel well, and the combination potentially could outperform D-T.potentially could outperform D-T.

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Field-Reversed Configuration Fusion Power Plants