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90-Day Single-Launch to Mars: A Case Study for The Fusion-Driven Rocket

90-Day Single-Launch to Mars: A Case Study for The Fusion-Driven Rocket. Anthony Pancotti John Slough, David Kirtley, George Votroubek, Christopher Pihl MSNW LLC, Redmond, WA 98052. FISO  Telecon  09-­‐25-­‐13. 1. 2. 3. 4. Background Mission Architecture Design Spacecraft Design

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90-Day Single-Launch to Mars: A Case Study for The Fusion-Driven Rocket

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  1. 90-DaySingle-LaunchtoMars: ACaseStudyforTheFusion-DrivenRocket AnthonyPancotti JohnSlough,DavidKirtley,George Votroubek,ChristopherPihl MSNWLLC,Redmond,WA98052 FISO  Telecon  09-­‐25-­‐13

  2. 1. 2. 3. 4. Background MissionArchitectureDesign SpacecraftDesign FusionPhysics 2  

  3. Why  We  Are  Not  on  Mars  Yet?   Takes  too  long   Safety   Costs  too  much   Direct  cost   Radiation  exposure   Cancer  risk   Bone  &  muscle  loss   Mental    fatigue   Increased  risk  of   Operational  costs   Complexity   Pre-­‐deploy  assets   Space  assembly   critical  failure   Launch  costs   Large  space     structures   Huge  fuel   Mass   Governmental  support   Political   Public  interest   Solution:  New  method  of  propulsion  is  needed   Short  trip  time   Reduced  IMLEO   High   ()  High  Exit  Velocity  (Isp) 3  

  4. TheFusionDrivenRocket (a)Thinhoopsofmetalaredrivenattheproperangle andspeedforconvergenceontotargetplasmoidat thrusterthroat.TargetFRCplasmoidiscreatedand injectedintothrusterchamber. (b)TargetFRCisconfinedbyaxialmagneticfieldfrom shelldrivercoilsasittranslatesthroughchamber eventuallystagnatingatthethrusterthroat (c)Convergingshellsegmentsformfusionblanket compressingtargetFRCplasmoidtofusion conditions (d)Vaporizedandionizedbyfusionneutronsand alphas,theplasmablanketexpandsagainstthe divergentmagneticfieldresultingdirectedflowof themetalplasmaoutofthemagneticnozzle. SchematicoftheinductivelydrivenmetalpropellantcompressionofanFRC plasmoidforpropulsion 4  

  5. Magneto-­‐Inertial  Fusion   Two  Approaches   Shell  (liner)  implosion  driven  by  B  from  large   axial  currents  in  shell.     Liner  implosion  from  j  x  B  force  between   external  coil  and  induced  liner  currents     Foil  Liner  Compression   FRC   plasmoid   FRC   Injector   FDR   Advantages:   Magnetic  Nozzle   Liner     Driver  System   MTF     Issues:   Extremely  low  inductance  load  difficult  to  drive   (massively  parallel  HV  caps  and  switches)   Close  proximity  and  electrical  contact    major   collateral  damage  with  each  pulse   Small  FRC  must  be  formed  close  to  implosion   marginal  B  for  ignition  w  injector  destruction     Only  inefficient  2D  compression  possible   requires  much  larger  driver  energy       Large  driver  coil  easy  to  power  with  ample   standoff   Driver  electrically  isolated  from  liner  and   magnetically  from  fusion  process   Large  FRC  can  be  formed  external  to  implosion   with  abundant  B  for  ignition   Full  3D  compression  can  be  realized  for   efficient  compression  and  translation     5   John  Slough,  David  Kirtley,  George  Votroubek,  and  Chris  Pihl, Lithium  Liner  Compression  of  an  FRC  Plasmoid,  20th  ANS  TOFE,  Aug  2012   -­‐Driven  

  6. FDRoffersthefirstrealistic approachtofusion-basedpropulsion 1   2   3   4   5   6   6  

  7. 1. 2. 3. 4. Background MissionArchitectureDesign SpacecraftDesign FusionPhysics 7  

  8. MissionStudies 350 300 250 200 150 100 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 FusionAssumptions: Ionizationcostis75MJ/kg CouplingEfficiencytolineris50% Thrustconversiont~90% Realisticlinermassare0.28kgto0.41kg CorrespondstoaGainof50to500 IgnitionFactorof5 Safetymarginof2:GF=GF(calc.)/2 Higherfusiongain andlongertriptimes resultinhigher payloadmassfraction FusionGain PaylodMassFraction PayloadMassFraction 50 200 0 0.8 MissionAssumptions: MassofPayload=61MT Habitat31MT 20 406080 TripTime(Days) 100 120 Aeroshell16MT DescentSystem14MT SpecificMassofcapacitors~1J/g SpecificMassofSolarElectricPanels200W/kg Tankagefractionof10%(tanks,structure, radiator,etc.) 0.7 0.6 0.5 0.4 0.3 150 100 Burntimeof~10days isoptimal PayloadMassFraction TotalGain PaylodMassFraction Payloadmassfraction=PayloadMass/Initial Mass SystemSpecificMass=DryMass/SEP(kg/kW) AnalysisforsingletransitoptimaltransittoMars FullpropulsivebrakingforMarsCapture-no 0.2 0.1 0 50 204060 BurnTime(Days) 80 aerobraking Anthony  Pancotti,  John  Slough,  David  Kirtley,  Micheal  Pfaff,   Christopher  Pihl,  George  Votroubek,  Design  Architecture   for  the  Fusion  Driven  ,  AIAA  48th  JPC,  July  2012 8  

  9. DeterminingtheOptimalMarsMission Opposition-class shortsurfacestaytimesatMars typically30to90days relativelyshorttotalround-tripmissiontimes 500to650days Conjunction-class long-durationsurfacestaytimes 500daysormore longtotalround-triptimes approximately900days minimum-energysolutionsforagivenlaunch opportunity Bothoptionsarewelloutsidethecurrentpermissibleexposurelimitofradiation Missiondowndesignapproach Mission  Architecture  Goal   90  Transit  times  to  and  from  Mars   Adequate  stay  time  (30+  days)   Single  launch  (130  MT  IMLEO)   No  pre-­‐deployed  assets   DRA  5  Payload  mass  (63  MT)   Full  propulsive  MOI  &  EOI   Reusable  spacecraft   (1)shortestoverallmissiontoreducethe associatedhumanhealthandreliability risks (2)adequatetimeonthesurfaceinwhich tomaximizethereturnofmission objectivesandscience (3)lowmissionmass,which,inturn, reducestheoverallcostandmission complexity missiondoesnot 9

  10. 210dayRound-trip MannedMarsMission 61MTpayload 27MT FusionEquation 83MT FDR   1  launch   134  MT   (IMLEO)   210  days   8000 6000 4000 2000 Isp(s) 0 100 200 FusionGain 300 15MT 134MT Refuel Re-crew Forfuture missions (May19,2018) DRA  5.0  (NTP),  9  launches,  848.7  MT  IMLEO,  1680  days   Isp=5000s PowerInput=180kW Gain200 Power(Jet)=36MW SpacecraftMass=15MT PayloadMass=61MT

  11. 210dayRound-trip(MissionDetails) 50 40 30 20 10 DeltaV(km/s) 0 0 50 100 150 200 250 Time(Days) 4 x10 15 10 5 Mass(Kg) 0 0 50 100 150 200 250 Time(Days) 11  

  12. NearBodyManeuvers Maneuver   V  (km/s)   T  (days)   Near  BodySimplified Near  Body Simplified TMI MOI TEI EOI Total   12.7   8.5   16.6   11.2   49.0   7.3   13.2   16.5   12   49.0   8.9   4.7   1.7   1.6   16.8   7.1   10.5   2.9   1.6   22.1   TMI TOI MOI TEI 12  

  13. FutureMissionStudies Mars SinglelaunchtoMars(OppositionClass) Missionrefinement LongStayMission(>500day)(ConjunctiveClass) Singletrip onorbitassembly Largers/c(fuellaunchedseparate) Pre-deploymissionarchitecture ClassicDRAstylewithpre-cursercargomission Ultra-fast(30day)transfers Jupiter Enterandexitgravitywell Moonmission NEO Samplereturn Redirection? 13  

  14. 1. 2. 3. 4. Background MissionArchitectureDesign SpacecraftDesign FusionPhysics 14  

  15. SpacecraftScaling Mission  Assumptions   Payload  mass   Spacecraft  mass   IMLEO   Earth  Orbital  Altitude   63  MT   15  MT   ~130  MT   407  km   Mars  park  orbit   Total  Mission  Time   Stay  Time     1   250  x  33793   210   30   sol   km   days   days   Mission     Architecture     Design   5000  s   8000 6000 4000 2000 Isp(s) Propulsion  Requirements   Isp   Jet  Power   Specific  Power   36  MW   240  W/kg   0 100 200 FusionGain 300 15  

  16. PowerSystemScaling Gain  of  200   2.4  MJ  Input  Energy  @  2  kJ/kg     1.2  MT  of  Capacitors   50%  space  de-­‐rating   1.8  MT  of  Energy  Storage   Solar  panels  have  flown  on  99%  of  all  space  mission.     ENERGY  STORAGE   36  MW  Jet  Power   Gain  of  200     180  kW  of  Input  power  OR  400  kW  at  Mars       200   W/kg   POWER  SOURCE   500  W/kg  to  1000  W/kg  are  speculated  for  the  future   Direct  energy  recovery  from  fusion  reaction  possible   2  MT  of  Solar  Panels   16  

  17. MassBudget Spacecraft  Component   Energy  storage3 Solar  Panels6 Switches  and  cables5 Spacecraft  structure1 Lithium  containment  vessel FRC  Formation2 Propellant  Feed  mechanism   Liner  driver  coils4 Thermal  Management Magnetic  Nozzle Margin   Mass  (MT)   1.8   2.0   1.8   3.8   0.1   0.2   1.2   0.3   1.1   0.2   2.5   Switches  and  cables  equal  to   energy  storage  mass   Simple  aluminum  coil,  but   most  likely  composites  with   We,  Be,  or  Cu  liners   Thermal  control,  10%  heat   rejection  @  1  kW/kg  with  a   margin  of  3X   Spacecraft  Mass     Total  Mass   15   63   56   134   FRC  formation  based  of  lab   equipment   Crew  habitat  (DRA5.0) Lithium  Compound  Propellant Propellant  Feed    roll  of  film    ring  formation  and  injection   20%  Margin   Payload  mass  fraction  46%   1.Fairings,supportstructure,communication,datahandlingACS,Batteries 2.HardwareresponsibleforformationandinjectionofFusionmaterial(FRC) 3.Capacitors(1.8MJ@1kJ/KG),switches,powerbus 4.Electromagneticcoilusedtodriveinductiveliner 5.Pulsedpowerelectroniccomponentsneedtochargeanddischargecapacitorbank 6.180kW@200W/kg 17  

  18. FusionDrivenRocketEngine ShadowShield MainCompressionCoils MagneticNozzle FRCFormation EngineTruss ShockAbsorbers Liner/PropellantInjector 18  

  19. SpacecraftLayout Considerations 36  caps   12  /ring   4.8  m     Energy  Storage  Packing   1.6  m   10.5  m   11.3  MT   Propellant  spool  Packing   5  m   45  m   19  

  20. FDRSpacecraftLayout SolarPanels Transit Habitat MarsLander Liner/Propellant FusionDrivenRocket Radiators Spline Truss Energy Storage

  21. FinalSpacecraftDesign 21  

  22. FutureDesignwork Support     Structure   Mission   Dependent X X X Magnetic     Nozzle  coils   Liner   converging   Mass   (MT) 3.8 0.1 0.2 1.2 1.8 0.3 1.8   2.0 1.1 0.2   Fusion   Dependent X X X X X X X X X Spacecraft  Component Spacecraft  structure Propellant  tank FRC  Formation Propellant  Feed   Energy  storage Liner  driver  coils Switches  and  cables Solar  Panels Thermal  Management Nozzle   TRL 4 5 4 2 7 3 6 8 5 2 Bias  magnets   Margin   Spacecraft  Mass   Crew  habitat Propellant Total  Mass 2.5   15 61   56 134 FRC  formation    region   Liner  Drive  coils   X X X X X X X Liner     start   For  a  more  accurate  spacecraft  design  and  total  launch  mass   A  more  defined  mission  and  fusion  conditions  are  need     22  

  23. 1. 2. 3. 4. Background MissionArchitectureDesign SpacecraftDesign FusionPhysics 23  

  24. Approach 1.Analytical   2.Computational   1D  Liner  Dynamic  +  Circuit   3D  Structural  compression   (ANSYS)   Neutronics   3.Experimental  Validation   24  

  25. Field  Reversed  Configuration  (FRC)    Magnetic  Field  lines  and  Pressure  Contours   Be rs rc xs Bvac r   rc Ls 2rs rs SOL   R   Ls z   Flux  Conservation      External  measurements  of  B  yield      FRC  separatrix  radius  rs(z),  FRC  length  Ls Bvac 1x2s Bext  volume,  position,  velocity Radial  Pressure  Balance      Simple  cross-­‐tube  interferometric        measurement  with  rs  from  yields  n  and  T   Axial  Pressure  Balance   With  above  obtain  plasma  energy,      Inventory,  confinement  times   Key   Equilibrium    Relations:   B2ext 20 1 x2s 2 P0 n0kT 1 FRC  equilibrium  constraints  and  the  diagnostic  measurements  that  together  with  the   equilibrium  relations  that  are  employed  to  determine  the  basic  parameters  of  the  FRC   equilibrium   25  

  26. Fusion  Based  on  Inductively  Driven  Liner   Compression  of  the  FRC   The  energy  within  the  FRC  separatrix  at  peak  compression  is  dominated  by   plasma  energy  that  is  in  pressure  balance  with  the  edge  magnetic  field  B0,  so  that   one  can  write:   B03 12 43 EL2MLvL 3n0kT03r0 r0 0 (1)   The  zero  subscript  indicates  values  at  peak  compression  where  rs~  r0and   magnetic  pressure  balance  (2n0kT0=  B02  /20).     dwell  time  Dat  peak   Fusion  energy  produced  in  the  FRC  during  the   compression:     4 vL 2r0 4 3 12 2 3 42 2 Efus 1.210 n0 v r0 1.110 n0T0 D (2)   where  n0  and  T0  are  the  peak  density  and  temperature,  and  where  the  liner  shell   dwell  time  at  peak  compression,  D,  ~  2r0/vL 26  

  27. Fusion  Based  on  Inductively  Driven  Liner   Compression  of  the  FRC  (cont.) The  usual  approximation  for  the  D-­‐T  fusion  cross  section  in  this  temperature   range:    1.1x10-­‐31  T2(eV)  was  also  assumed.  Pressure  balance,  together  with   expressions  (1)  and  (2)  yields  for  the  fusion  gain:   Efus EL ML l0 G B0 4.3x108M1L/2E11L/8 1.73103 where  l0  (=  2r0)  is  the  length  of  the  FRC  at  peak  compression.  The  last  expression   is  obtained  from  adiabatic  scaling  laws       and l0~r02/5~B01/5 EL~B02r02l0~B04/5  to  express  G  in  terms  of  the  liner  kinetic  energy  EL  and  mass  ML  only.     Fusion  Ignition  will  amplify  gain  by  large  factor.  It  is  estimated  that  the  total  fusion   gain  GF  ~  5-­‐10G.  For  a  large  margin  of  safety,  it  is  assumed  that:   GF  =  2.5G  or,   GF  =  1.110-­‐7  ML1/2  EL11/8 27  

  28. Comp-1DLinerCode SourceFreeRLCCircuit CircuitParameters R=3m L=20nH 420uF 40,000V LinerParameters r=0.41m w=6cm l=0.2mm dI dt dL dt dV dt V=L I +IR I=C 9 x10 changing   inductance   Solvedas2FirstOrderequations 0.015 0.01 0.005 1 0 -1 Thickness(m) LinerAcceleration(m/s2) 0 0.04 -2 2000 0 1 3 -4 x10 2 Time(s) Phase  change   0 1 2 Time(s) 3 -4 x10 Various  Current  waveforms   Ringing   Crowbar   Diode   Magnetic  flux  diffusion   Increasing   Cross-­‐section     Linerresistance() 0.02 LinerVelocity(m/s) 0 Latent  heat     12 Time(s) Resistivity  -­‐  (T)   Latent  heats   Radiative  cooling   0 1500 -2000 0 3 -4 x10 0 1 2 Time(s) 3 -4 x10 Energy  conservation   Dataforactualcoiland 0.4 0.2 1000 500 Temperature(K) LinerRadius(m) collectorplateused InFoilLinerCompression (FLC)Testbed 0 0 0 1 2 Time(s) 3 -4 x10 0 1 2 Time(s) 3 -4 x10 28  

  29. ANSYSExplicitDynamics®Calculations Three0.4mradius,5cmwide,0.2mm thickAluminumlinersconvergingonto astationarytesttarget. First3Dstructurecompressionof metallicliner Nogrossinstabilitieswereobserved duetothestructurerigidityofthe material Forcesarewellbeyondtheplastic deformationlimitofthematerial, resultinginauniformcompression Lowinternalenergyfromtheliner compressionwhichisdifferentfrom plasmaorthicklinercompression T=0µs T=40µs T=80µs T=120µs T=160µs T=195µs Linerbehavioragreedverywellwith1DLinerCode 29  

  30. FRCFusionatMSNW ofaHighTemperaturePlasmathroughMergingandCompressionof SupersonicFieldReversedConfigurationPlasmoids Fusion,2011 Fusion  with  this  technique  is  proven,  this  is  not  another  fantasy   $5  M  DOE-­‐funded  programs  demonstrated  high  field  compression   of  FRC  to  fusion  conditions   o o o o 2.3  keV  Deuterium  Ions   >100  microsecond  lifetimes  of  1E22  plasma   >1E12  D-­‐D  neutrons  created  in  this  program   At  only  1.2  Tesla!   FRC  programs  at  similar  size  demonstrated  >3  ms  lifetime   30  

  31. Experimental IDLUnityGainValidationExperimentatMSNW CADrenderingoftheFoil LinerCompression(FLC) testfacilityatMSNW 31   PictureoftheFDRvalidationexperiment constructionnowunderway.

  32. ExperimentalResults 40  cm  radius,  6  cm  wide,  0.4  mm  thick  Aluminum  liners   0.6 ANYSISMaxR 400   s     400   s     410   s     420   s     Exp.R(30349) Exp.R(30331) Exp.R(30351) ANSYSMinR 1DCodeR 410   s     420   s     0.5 0.4 0.3 0.2 ¼  Power   Aluminum  Liner     Testing  for  code   Validation       LinerRadius(m) 20  kV  |  840  F  |16  mil     0.1 430   430   0 s     s     0 1 2 4 5 3 Time(s) 6 -4 x10 440   s     450   s     460   s     440   s     450   s     460   s     10 8 6 4 2 1DCodeB Exp.B(30351) MagneticFieldinGap(T) 0 0 1 2 3 Time(s) 4 5 6 -4 470   s     470   s     x10 32  

  33. Summary Mission  Assumptions   Mission  Architecture  Goal   90  Transit  times  to  and  from  Mars   Single  launch  to  Mars  (130  MT  IMLEO)   No  pre-­‐deployed  assets   Payload  mass   Spacecraft  mass   IMLEO   63  MT   15  MT   130  MT   63  MT  Payload  mass   Full  propulsive  MOI   Full  propulsive  EOI   Reusable  spacecraft   Earth  Orbital  Altitude   Mars  park  orbit   Total  Mission  Time   Stay  Time     407   1   210   30   km   sol   days   days   Halfway  through  Phase  2  NIAC   Mission  architecture   Propulsion  Requirements   Spacecraft  Design     Fusion  Physics   Analytical   Computational   Experimental   Isp   Jet  Power   Specific  Power   Gain     5000  s   36  MW   240  W/kg   200   33  

  34. BACK-UPSLIDES 34  

  35. EstimatedTotalEquivalentDoses Currenttechnology (210days) NTP/NEP (150days) FusionDriven Rocket (30days) Marssortiemission (30daysstay) LongstayatMars base(525days) Solidbars calculationforspacecraftwithaminimumshield(5g/cm2Al) Dashedbars calculationsforathickshield(20g/cm2Al) Thecareerlimitis400mSvfora25yearoldfora3%riskoffatalcancer Thereisstillgreatuncertaintyastowhattheactualriskisforlongterm lowlevelexposure 35  

  36. Lindl-­‐Widner  Diagram  with  Magnetic  Field     Confinement  Of  the  Fusion  Alphas   FDR   The  BRform  of  the  L-­‐W  diagram.  Ignition  curves  for  different  product  BR.   When  the  BR  parameter  exceeds  the  threshold  value,  the  dT/dt  >  0  region  extends  to   36   infinitely  small  Rand  ignition  becomes  possible  at  any  R.  

  37. AnticipatedParametersfrom FDRValidationExperiment FRCadiabatic scalinglaws InitialFRCsize,temp densityandenergy FRClifetime >>dwell~4s Inexperiment,FRC radialandaxial compressionswould occursimultaneously Finalfield similarto thatachieved inseveral flux compression expts. SubMJFRC Requiresonly 33%bankeff. FinalFRCparametersyieldafusiongainG=1.6(ML=0.18kgAl) 37

  38. Material  Constraints  with  Inductively   Accelerated  Liners   The  material  properties  relating  to  this  resistive  heating  (electrical   conductivity,  melting  point,  heat  capacity,  etc.)  can  be  characterized  by  a   parameter  gM tm22 0 I  -­‐  current  flowing  through  the  material  cross-­‐sectional  area   Idt gMA A  =  w ,  where  w  is  the  liner   liner  thickness.     The  driving  force  is  simply  the  magnetic  pressure  (B2/2µ0)  applied  over  the   surface  area  of  the  metal  facing  the  coil  when  in  close  proximity  to  the   driving  coil.     The   reasonably  approximated  as  B  =  µ0I/w.     One   vm(m/s)2.5x10 (mm) Aluminum6061 4 Al vm(m/s)1.6x104 (mm) Lithium Li 38  

  39. ANSYSMaxwell®Calculations ofthe3DElectromagneticFields R B(T) 8 4 0 Solutionfora0.4mradiuscoildrivinga6cmwide,0.2mmthickAlliner. ThecircuitwasbasedonthecapacitorbankcurrentlyavailableattheUW PlasmaDynamicsLaboratory. Thespatialforcesonthelineratvarioustimesandradiiarecalculatedand usedasinputintothedynamiccalculationsimilartotheoneshownabove. Mutualinteractionbetweencoilsandlinerswillalsobeinvestigated. 39

  40. TheoreticalValidationofKey FDRElements(peerreviewedpapers) Importanceof3Dcompression Superiorityofhigh FRCtarget Magneticfieldlimitsthermaland particleloss-evenwith(cold) wallconfinementand >1 Ignitionpossiblewithmagnetized plasmawhereR<<1butBR> 60T-cm. Magneticfieldwellwithinrange oflargerFRCs. Methodforproducing3Dliner implosionswithstand-off GenerationofFRCplasmatarget withsufficientmagnetizationand confinementforignition Methodforefficientconversionof plasma,radiation,andfusion energyinamannerthatprotects 40 FusionBasedontheInductively-DrivenLithiumLiner CompressionofanFRCPlasmoid JohnSlough,DavidKirtley,AnthonyPancotti,ChristopherPihl, GeorgeVotroubek (SubmittedtoJournalofFusionEnergy2012) andmagneticallyisolatesreactor

  41. TheoreticalValidationofKey FDRElements(peerreviewedpapers) Demonstratedinductively drivenlinercompression ofBzfields>1Mbar Demonstratedthestableformation, mergingandmagneticcompressionof theFRC FRClifetimebetterthanpreviousscaling DemonstratedsuccessfulFRCliner compressionwithaxenonplasmaliner Hopetopublishinthenearfuture! 41 Experimentaldemonstrationoffusiongain withinductivelydrivenmetalliners

  42. Magneto-­‐Inertial  Fusion   Best  of  Both  Worlds   Solid  stars  signify  fusion  gain  conditions  w  Ti  =  Te  =  10  keV   1012 109 Plasma  Energy  (J)   Stored  Energy  (J)   106  10 10320                              1022                        1024                        1026                        1028                          1030                        1032 Plasma  Density  (m-­‐3) ITER  MFE  Issues:   Enormous  magnetic  energy  requires   Cryogenic  Magnets   Low  power  densities  leads  to  large  scale,   capital  and  development  costs   Devastating  transient  instabilities  defy   solution     NIF  ICF  Issues:   Enormous  storage  energy  (~400  MJ)  due  to   very  low  driver    efficiency   Even  with  stand-­‐off  ,  reactor  wall  and  is   bombarded  by  primary  fusion  products   Intricate  and  minute  target  with  sub-­‐nsec   timing  make  for  challenging  technologies         42  

  43. 1DLinerCode:Maxwell®Data -6 x10 3 Dataforactualcoiland 2 1 0 collectorplateused InFoilLinerCompression (FLC)Testbed TotalInductanceofcoilwith lineratvariouslocations.Liner inductancewasdetermined theoretically CoilInductance(H) 0 0.1 0.2 0.3 0.4 0.5 LinerRadius(m) -5 x10 PhysicalParameters 1.5 Bavg Ic AverageMagnetfieldinthegap betweencoilandlinerdivided bythecurrentinthecoilfor variouslinerlocations B(I,R)= 1 0.5 MagneticFieldasfuncitonofRandI 0 0 0.1 0.2 0.3 0.4 0.5 LinerRadius(m) -7 x10 Solid-­‐liquid     transition   6 4 2 Accuratedefinitionofresistivityof AluminumbasedonNISTdata. Dataonlywentto2000K.Data waslinearextrapolatedoutto Resistivity(Ohms/m) vaporizationtemperature 0 0 500 100015002000 Temperature(K) 2500 3000 r=0.41m w=6cm l=0.2mm 43  

  44. 1DLinerCode ConservationofEnergy R=Rc+Rm+RKE+RT equivalent resistancevalue needtoremove energyequalto ohmicdissipation (heating)oftheliner Resistanceofthecoil Resistanceofthecircuit equivalentresistance valuetoremovethe energyfromthecircuit equaltothekinetic energygainedbythe liner 5 x10 3.5 EKE ETherm Ecap Ecoil Eresist Ecirc Etotal Einnerfield Ecap 3 2.5 2 1.5 1 0.5 0 Energyrecovery Allthermallosses drivecurrent innerfieldcurrent Pressurebalanceofinner andouterfields Energy(J) -0.5 0 1 Time(s) 2 -4 x10 44  

  45. ResearchPlan TechnologyRoadmapfortheFusionDrivenRocket 2015 2020 2025 2030 180W/kg 300W/kg 600W/kg 1000W/kg SolarPower EnergyStorage 1kJ/kg 2kJ/kg Gainof200 Spaceflight Charging RepRate>0.01Hz LiLiner Gain<1 RL=0.4m EL=0.5kJ ML=0.18kg D-DOperation SinglePulse $10M/year Shielding Thermal FRCFormation Magnetics Propellant Chamber/Nozzle FDRENGINE (CompleteSystem) Gainof40 RL=1m EL=3.5MJ RepRate>0.1Hz ThrusterwithNozzle Milestones ConceptValidationExperiments SubscaleGroundDemonstration Full-ScaleGroundPrototype In-SpaceDemonstrationMission MannedMarsMission MannedMarsSpaceflightProgram AlLiner PhaseII Gain>5 RL=0.4m EL=2MJ ML=0.38kg D-TOperation RepRate>0.01Hz $50M/year PhaseI Technology Demonstration Mission GameChanging TechnologyDevelopment TRL NIAC NASAMarsFlightProgram

  46. AnalyticalModel(FusionSide) From  action   Integral  constraint   where  RL=  1.2  m,   w  =  0.15m   Energy  loss  in   ionization  of  liner  (~75   MJ/kg)   Eout=fusionenergy+Ein EL=linerkineticenergy Ein=EL+EFRCEL ML=massofliner vL=velocityofLiner C=EL/Ecap=0.5 T=thrustefficiency=0.9 Ek=kinetic(Jet)energy Min.MLrequiredto trapfusionproducts: 0.28kg DropoffinIspatlow gainsisdueto ionizationlosses Forknown LinerMass a SpecificImpulse isdetermined Isp=specificimpulse Isplinksfusionconditionswithmissionequations 46  

  47. AnalyticalModel (Missionside) RocketEquations MR MassRatio 7Equations 7Unknowns V Ispg0 Mi Mf MfFinalmass MiInitialmass MPPropellantmass MsStructuralmass fFrequency e MR MR capSpecificmassofcapacitors Mf MPLMS MPLMSMP Specificmassofsolarpanels Solarpanelpower SEP PSEP Mi Ispfromfusionconditions MP MLfT Ein cap Ein PSEP SEP PSEP f Ms 0.1MPL DeltaVrequirementasafunctionof triptime:SolutiontoLambert Problem ItisassumedthatinitiallyFDRemployssolarpanelsforhousekeepingpower Eventuallyitwouldbederiveddirectlyfromnozzlefluxcompression

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