Design of MIRIS and Hyperion SMRs for use inSMRs for use in
Vista Class Cruise VesselsVista Class Cruise Vessels
Dr Paul R Chard-TuckeyDr Kirk Atkinson
December 1st 2011College of Management and Technology
December 1st 2011
Vista ClassVista Class300m X 30m 91,000GRT 24knots
16 decks 1,000 crew 2,000 passengers
63MW diesel
3,000t heavy fuel1
150t marine gas oil
12t per hour
Noordam Queen Elizabeth Queen Victoria
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1. Reuters 3 Nov 11
Study ScopeStudy Scope
• Navalisation & Economics ~ PC-T• Core Design & Reactor Physics ~ Kirk• Core Design & Reactor Physics Kirk• Shielding and Materials ~ Kirk• Thermal Hydraulics and Dynamics ~ PC-T
S f t d S it PC T• Safety and Security ~ PC-T
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Candidate SMRsCandidate SMRs
• MIRIS – Integrated PWR• Hyperion – Liquid Metal Fast ReactorHyperion Liquid Metal Fast Reactor
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MIRISMIRISI t l PWR• Integral PWR
• Uranium oxide fuelled• 120 MWt output• Overall height 10.3 mg• Inner diameter 4.1 m• Eight once throughEight once through
type SGs and MCPs• Integral PressuriserIntegral Pressuriser• 36 MWt nat circ
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HyperionHyperion
• LMFR• 70 MWt• Uranium Nitride fuel• Lead Bismuth coolant• Lead Bismuth coolant• Unpressurised• He Gas system• No intermediate loop
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http://www.nrc.gov/reactors/advanced/hyperion.html
RequirementsRequirements• Offer alternative power sourceO p• Design to be supplied with modern design
safet casesafety case• Licence Conditions• Achieve in a cost effective manner
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RequirementsRequirements• Performance capability• Refueling/replacement• High integrity and reliability of electricalHigh integrity and reliability of electrical
systemMinimal manning• Minimal manning
• Dose Targets < BSL• HAZID• Adequate security• Adequate security
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Comparison CriteriaComparison Criteria
• Incorporated into decision matrix• Weighting factors out of 5Weighting factors out of 5• Scoring factors out of 10
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Navalisation and EconomicsNavalisation and Economics
• Power Requirements & Operating CyclePower Requirements & Operating Cycle• Manning Requirements • Secondary & Electrical System Designs• Reactor Protection• Reactor Protection• Economics• Summary
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Power RequirementsPower Requirements
• Ship hull and appendages modelling using NavCad code
• Holtrop model utilised• Assumptions made:Assumptions made:
– Two azimuth thrusters– Two stabiliser finsTwo stabiliser fins– Seawater temperature of 15 oC– Sea state 2 wind conditions– Sea state 2 wind conditions – Centre of buoyancy 2 % aft
• 35 Mw @ 24 kts
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• 35 Mw @ 24 kts
Power Requirementsq• Thermal Power
Including losses and hotel load– Including losses and hotel load
180
200
120
140
160
80
100
120
Power (MW)Th HypTh MIRIS
20
40
60Th MIRIS
01 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Speed (Knots)
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p ( )
Power RequirementsPower Requirements
• MIRIS max output: 120 MWt• MIRIS at 24 knots requires 172 MWtq
• Hyperion max output: 70 MWt• Hyperion max output: 70 MWt• Hyperion at 24 knots requires 129 MWt
• Both designs would require 2 plants to meet the total power demand
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Operating CycleOperating Cycle
• Based over a three year period• Cruises include:
– Mediterranean – North Europep– Fjords & Baltic – Caribbean & Mexico– Around the World– North America & CanadaNorth America & Canada– Transatlantic Crossing
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Operating CycleOperating Cycle
• Effective Full Power Days (EFPD) calculated over 7 year period: 1508 EFPDy p
F l C ti C l l ti• Fuel Consumption Calculations:– MIRIS: 3020 EFPD with 634 kg U-235g– Hyperion: 4300 EFPD with 902 kg U-235
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Secondary System DesignsSecondary System Designs
• Full electric propulsion incorporated into both designs
• Secondary systems identified for both designsSecondary systems identified for both designs
Secondary coolant flow rates calculated for both• Secondary coolant flow rates calculated for both designs
MIRIS 298 5 k / f 100 %– MIRIS 298.5 kg/s for 100 % power– Hyperion 29.4 kg/s for 100 % power
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EconomicsEconomics
• Vessel of this size produces 712 kg of CO2per kilometre travelled p
T diti l f l t i i f• Traditional fuel costs in region of $18,000,000
N IMO l ti ld lt i• New IMO regulations could result in $3,500,000 extra in fuel costs
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EconomicsEconomics
• Worst case ship built cost estimated at €800,000,000, ,– Including secondary systems, shielding and
protection systemsprotection systems
Shi ld t fit ft 10• Ship would return a profit after a 10 year period – Based on current revenue figures
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SummarySummary
• Hyperion best meets Navalisation and Economics requirements
• Hyperion technology readiness low• Hyperion technology readiness low– MIRIS would be better option for 5 to 10 year
implementation timelineimplementation timeline
I i fit t hi ith l f• Increase in profits to ship owner with removal of traditional fuel costs
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Core Design and Reactor Physics
• Core Descriptionsp• HPM Stochastic Modelling Process• HPM Deterministic Modelling Process• HPM Deterministic Modelling Process• Analysis of HPM Core Characteristics
S f K Fi di• Summary of Key Findings• Conclusions
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Hyperion Stochastic Modellingyp gSecond Stage• Development of simple
3D homogeneous core model using MONK Monte Carlo neutronics code
• Value for keffectiveeffective (k-value) validated against Hyperion g yPower Gen data
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Hyperion Stochastic ModellingHyperion Stochastic ModellingThird Stage – Heterogeneous Model
HPM Heterogeneous MONK Model Improved HPM Heterogeneous MONK Model
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HPM Heterogeneous MONK Model Improved HPM Heterogeneous MONK Model
Analysis of HPM Core Characteristics
T t C ffi i t f R ti it• Temperature Coefficient of Reactivity• Axial and Radial Flux Profiles
Th h Lif R ti it P fil (i lif )• Through-Life Reactivity Profile (inc. lifespan)• Void Coefficient of Reactivity• Power Density• Rod Worth
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Temperature Coefficient of Reactivity, αT
Effect on Reactivity per Degree Change in Coolant and Fuel Temperatures
HPM MIRIS
-1.513E-05 -5.912E-4
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Final αT Results
Radial Flux Profile
Q t di l fl fil f f ll
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Quarter-core radial flux profile for a fully un-rodded HPM core arrangement
Through-Life Reactivity
HPM through-life reactivity profile
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HPM through life reactivity profile
Summary of FindingsHyperion MIRIS
Key Advantages • Less high level waste • Strong negative αTy g g• Negligible poison inventory • Greater lifespan
g g T
• Strong negative void coefficient
• Proven PWR• High power density • Proven PWR technology
Key • Novel fuel type • Significant axial Disadvantages • Rounded flux profile
• Weak αT
• Significant power peaking
power peaking• Lifespan limited by
short and long • Significant power peaking• Immature design
lived poisons
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Conclusions
• MIRIS identified as the most suitable of the two designs to satisfy the requirementy q
• Limited amount of information from HPG may have had a significant impact on the analysis
• Useful information fed back to Serco for the development of WIMS 10a
• First Fast Reactor Analysis of its type conducted within the Nuclear Department.
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Shielding & MaterialsShielding & Materials
• MaterialsD R i t• Dose Requirements
• Expected Gamma Dose Ratesp• Shielding Options
MCBEND• MCBEND• ConclusionsConclusions
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Lead Bismuth CoolantLead Bismuth Coolant• Opaque to gamma radiationp q g
•Transparent to neutrons
• Low melting point 124C
• High boiling point 1670C
• High thermal capacity
Mi i l th l i /• Minimal thermal expansion / contraction
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• Allows natural circulation
Uranium Nitride FuelUranium Nitride Fuel
• High melting point 900Cg g p
• Excellent thermal conductivity c.f. UO2
• Difficult to prepare• Difficult to prepare
• None prepared to date for p pthe Hyperion programme
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Dose RequirementsDose Requirements
• No breach of legal limits
• No dose above background levels to t l ( 0 15 S /h )guests or normal crew (≤0.15 µSv/hr)
• Minimise doses to reactor operators
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Expected Doses Point SourceExpected Doses – Point Source• Standard dose MIRIS 4.93E+17 Bqcalculations using a point source
Att ti th h i
Hyperion 5.02E+17 Bq
Kr-85 I-135• Attenuation through air only
• Very high dose rates
Kr-85m Xe-133Sr-90 Cs-134I-131 Cs-137• Very high dose rates
Dose Rate (Sv/Hr) in: Air
I-133 Ba-140
(S / )
At (m): 0.1 0.5 1 5 10
MIRIS: 8.20E+06 3.28E+05 8.20E+04 3.28E+03 8.20E+02
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Hyperion: 9.49E+06 3.79E+05 9.49E+04 3.79E+03 9.49E+02
Shielding MaterialsShielding Materials• Requirement to attenuate against bothRequirement to attenuate against both
gamma radiation & neutronsHi h D it M t i l G• High Density Materials – Gamma
• High Hydrogen Content – NeutronHigh Hydrogen Content Neutron• Three Initial Options Considered:
― All shielding at the compartment edge― All shielding as a “sarcophagus” ― A combination of the above
• 6000 tonne target definedCollege of Management and Technology
• 6000 tonne target defined
Option OneOption One
•12.5 cm Pb shield at the outer edge
34 5 P l th hi ld•34.5 cm Polythene shield
•Mass Pb = 2462 tonnes•Mass Pb = 2462 tonnes
•Mass Polythene = 538 tonnesy
•Total Mass = 3000 tonnes
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CompromiseCompromiseA combination of the t o options• A combination of the two options:― 50 cm Lead & 50 cm Polythene Main Shield
10 L d & 10 P l th RC Ed― 10 cm Lead & 10 cm Polythene RC Edge Shield
• Total Shield Mass:• Total Shield Mass:― MIRIS – 3892 tonnes per reactor
Hyperion 2722 tonnes per reactor― Hyperion – 2722 tonnes per reactor
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MCBENDMCBEND
• A Monte Carlo program for general radiation transport solutionsp
• Sources to consider:P t G– Prompt Gamma
– Prompt Neutron– Delayed Gamma– Coolant GammaCoolant Gamma
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MIRIS ZonesMIRIS - ZonesPressuriser Spool MCP
I l t / O tl tSteam Generator
Inlet / Outlet Pipes
Coolant Zone
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Active Core
Hyperion ZonesHyperion - ZonesInlet / Outlet Pipes
Coolant Zone
Central Void
RPV Edge
Water JacketActive Core
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ConclusionsConclusions• MIRIS uses well understood materialsMIRIS uses well understood materials
choicesH i t i l i k• Hyperion materials require more work
• Both reactors meet set dose requirementsq
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Thermal Hydraulics and Reactor Dynamics
• Methodology
Thermal Hydraulics and Reactor Dynamics
Methodology• Normal Operation
– Load Following– Self Regulatingg g– Xenon 135 Influences
Loss of Flow & Natural Circulation• Loss of Flow & Natural Circulation• Loss of heat sink• Summary
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Methodology MIRIS & HyperionMethodology MIRIS & Hyperion
• Hand calculations:– Natural circulation velocity– Axial coolant temperature profiles– Radial coolant/fuel centreline temperature profiles– Axial pressure profiles
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Methodology MIRIS & HyperionMethodology MIRIS & Hyperion
• Modelling – MATLAB/Simulink:– Six Group Point Kinetics– Thermal Hydraulics
o Plus radial coolant/fuel centreline temperature model
– Heat Removal System– Thermal feedback system– Flux model– Xenon 135 numeric density model– Xenon 135 reactivity influence model
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Methodology MIRIS & HyperionMethodology MIRIS & Hyperion• Modelling – MATLAB/SimulinkModelling MATLAB/Simulink
FluxXe-135 Numeric
Xe-135 Reactivity
ThrottlePosition
2o HeatBalance dTs
dT
FluxNumeric Density
ReactivityInfluence
Position Balance
ReactorKinetics
ThermalHydraulics
LoopDelay
1o HeatBalance
RodPosition
dTh
LoopDelay
ThermalFeedback
dTc
DelayFeedback
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Power Reactor Loop Heat Removal
Methodology MIRIS & HyperionMethodology MIRIS & HyperionX 135 N i D it M d l• Xenon 135 Numeric Density Model
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Normal Operation –Steady State Conditions
Parameter SI Unit MIRIS HyperionSpecific Heat Cp J/kg.K 5896.48 154.89±14Mass Flow Rate mdot kg/s 3000 2100.6759Prandtl Number Pr - 0.92 0.014Reynolds Number Re - 7.85E5 4.67E4Nusselt Number Nu - 1.15E3 22.70Coolant Thermal Conductivity Kf W/m.K 0.53 14.5Fuel Thermal Conductivity Ks W/m.K 3.5 20Average Temp Tave = Tb K 588.39 773.15Axial Change in Temp Th - Tc K 6.78 215.14Clad Surface Temp Ts K 625.10 785.26p s
Fuel Surface Temp Tf K 662.44 810.13Fuel Centreline Temp Tm K 1140.23 1001.16
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Differences in ResponseDifferences in Response
• Primary System Design• Delayed Neutron Fractiony• Prompt Neutron Generation Time• Feedback Coefficient ‘α ’• Feedback Coefficient αT
• Thermo Physical Properties• Fuel Material Properties
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SummarySummary
• Normal Operation• Loss of Flow• Natural Circulation
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Safety and SecuritySafety and Security
• Severe accident analysisS it• Security
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Severe Accident AnalysisSevere Accident AnalysisId tif hi h l t t f d i• Identify which elements to carry forward in accident dose calculations
• Establish and identify core inventory• Establish and identify core inventory• Gain confidence in results by comparison
methodsmethods• Identify plausible accident scenario• Identify release into containmentIdentify release into containment• Establish containment conditions• Establish leakage from containmentEstablish leakage from containment• Calculate dose rates in adjacent compartments
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Isotopes Activity equationIsotopes Activity equation
• Krypton 85 and 85m
• Activity = FY(1-eλt)• F = fission rate
• Iodine 131-135F fission rate
• Y = yield• Strontium 90• Caesium 134 and
• λ = decay constantCaesium 134 and 137X 133 d• Xenon 133 and 135
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• Barium 140
ORIGENORIGEN
• Water cooled reactor specific• Solves ODE from set starting conditionsSolves ODE from set starting conditions• Uses look-up tables of cross-sections
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Containment ConditionsContainment Conditions
• FP released as aerosol• Steam and water vapour presentSteam and water vapour present• FP inflow• FP removal • FP outflow• FP outflow
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Finite Element Aerosol Simulation Tool (FEAST)• Time• Mass inflowMass inflow• Mass outflow (used in dose calculations)• Mass to walls• Mass suspended• Mass suspended
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FEAST ResultsFEAST ResultsAerosol mass for 1mm leak
32 kg in RC
1.00E+01
1.00E+02
1.00E-01
1.00E+00
g)
mass in
mass out
1.00E-03
1.00E-02
Mas
s (k
g
masssuspended
1.00E-05
1.00E-04 mass to walls
1.00E-060.00E+00
2.00E+04
4.00E+04
6.00E+04
8.00E+04
1.00E+05
1.20E+05
1.40E+05
Time (s)
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Time (s)
0.02 kg release
Dose Results 1mm Diameter Leak
Exposure time (s)
Cloud shinedose (Sv)
Inhalation dose (Sv)
Skin dose (Sv)
3.00E+02 2.71E-05 6.85E-04 3.60E-02
3.60E+03 1.70E+00 2.58E+01 1.37E+033.60E 03 1.70E 00 2.58E 01 1.37E 03
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International Nuclear SecurityInternational Nuclear Security
• IAEA guidance• IAEA conventionsIAEA conventions• Licensee’s responsibility• Reduced protection at sea
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Security at SeaSecurity at Sea
• Physical barriers• Ship designShip design• Defence in depth• Armed guards1
• Employee vetting procedures• Employee vetting procedures
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1. FT 13 Oct 11
Final SelectionFinal SelectionProject Pillar MIRIS Weighted HPM Weighted j g
Scoreg
Score
Navalisation and 142 169Navalisation and Economics
142 169
Core Design and Reactor 114 64Physics
Shielding and Materials72 81
Shielding and Materials
Thermal-Hydraulics and Dynamics
44 44
Safety and Security160 162
Totals: 532 520
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Totals: 532 520
Project InterfacesjOUTPUTSINPUTS
Safety & Security•Reactor Protection Requirements
O ti l P fil
Safety & Security•Plant Reliability Figures
•CSF Breakdowns •Operational Profile
Shielding and Materials•Refuelling Process
•CSF Breakdowns
Shielding and Materials•Operational Doses Refuelling Process
•Manning Requirements
Thermal Hydraulicsd D i
p•End of Life Doses
Thermal Hydraulicsand Dynamics
NAVALISATION & ECONOMICS
and Dynamics•Secondary Pump Flows
•Secondary System Designs
and Dynamics•Size of Prim/Sec
Heat Transfer System
Core Design & Reactor Physics•Reactor Protection System
•Uranium Fuel Costs
Core Design & Reactor Physics•U-235 Loadings•Burn-up Rates
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Normal Operation –Steady State Conditions
Parameter SI Unit MIRIS HyperionParameter SI Unit MIRIS HyperionReactor Power P W 120e6 70e6Operating Pressure poperational bar 155 1Coolant Density ρcoolant kg/m3 694.46 10050y ρcoolant gSpecific Heat Cp J/kg.K 5896.48 154.89±14Coolant Velocity U m/s 3.31314 2Mass Flow Rate mdot kg/s 3000 2100.6759P dtl N b P 0 92 0 014Prandtl Number Pr - 0.92 0.014Reynolds Number Re - 7.85e5 4.67e4Nusselt Number Nu - 1.15e3 22.70Convective Heat Transfer h W/m2.K 2.18e4 1.08e5Cold Leg Temp Tc K 585 665.58Hot Leg Temp Th K 591.78 880.72Average Temp Tave = Tb K 588.39 773.15A i l Ch i T T T K 6 78 215 14Axial Change in Temp Th - Tc K 6.78 215.14Clad Surface Temp Ts K 625.10 785.26Fuel Surface Temp Tf K 662.44 810.13Fuel Centreline Temp Tm K 1140.23 1001.16
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p mRadial Change In Temp Tm - Tb K 551.84 228.01
Secondary System StudySecondary System Study C i i M h i l El i lCriteria Mechanical Electrical Cost 2 2
Size and Weight 2 5g
Efficiency 3 5
Shock 2 4
Control Complexity 4 2
Reliability 3 4
A il bili 2 4Availability 2 4
Manning 3 5
Maintenance 3 5Maintenance 3 5
Noise 4 5
TOTAL 28 41
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Power RequirementsPower Requirements
• Hand calculations using Flat Plate MethodFD = 0.5pU2CDLBD p D
CD = 0.0986/[log10(UL/V)-1.22]2
FD = Frictional drag p = Seawater densityp yU = SpeedCD = Drag coefficient L = LengthB = BreadthV = Kinematic viscosity of seawater
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V = Kinematic viscosity of seawater
Power RequirementsPower Requirements
N f U 235 t St t f Lif• No. of U-235 at Start of Life– (Mass of U-235/U-235 Atomic Weight) x Avogadro’s
N bNumber
• No. of U-235 at End of Life– U-235 at SOL x e-(Capture Cross-Section x Flux x Time)
• No. of atoms available for fission:– U-235 at SOL – U-235 at EOL
• Effective Full Power Days: ec e u o e ays– (Atoms available for fission/Atoms required) x 3600 x
24
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Manning RequirementsManning Requirements
• Operators required to operate plant, carry out maintenance and perform defect repair
• Shift Rotation: 3 shifts with 1 standbyShift Rotation: 3 shifts with 1 standby
Shift Manning: 1x Senior Operator 2x Operator• Shift Manning: 1x Senior Operator, 2x Operator
• Optimum option for safety and cost
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Manning RequirementsManning Requirements
Manning Shift Annual Cost External gOption Option Company
Annual Cost 1 1 £1 971 000 £2 463 7501 1 £1,971,000 £2,463,750
4 2 £917,000 £1,146,250
5 3 £630,500 £788,125
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Electrical System DesignElectrical System Design
• AC system with novel Low Loss Concept (LLC) design
• Installation of LLC transformers– Phase shifts windings to remove unwanted current g
harmonics, thus improving efficiency• Azimuth Thrusters
– Z-Drive design with AC synchronous motor• Emergency GeneratorsEmergency Generators
– Diesel Generators with 6.5 MW capacity– 200 tonnes of Marine Diesel Oil required
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– 200 tonnes of Marine Diesel Oil required
Reactor ProtectionReactor Protection
• Critical Safety Function breakdowns reviewed
• Reactor protection system requirements defined and categorised in terms of nuclear safetyand categorised in terms of nuclear safety
N l t h l i• Novel technologies– High Integrity Displays– Equipment Health Monitoring
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Reactor ProtectionReactor ProtectionS f t I t it L l L D d M d f O tiSafety Integrity Level Low Demand Mode of Operation
(Failure to perform function per hour)
4 >= 10-5 to 10-4
3 >= 10-4 to 10-3
2 >= 10-3 to 10-2
2 11 >= 10-2 to 10-1
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SummarySummarySelection Weighting MIRIS HPM MIRIS HPM Criterion
g gFactor Score Score Weighted
ScoreWeighted Score
O ll C t 5 6 8 30 40Overall Cost 5 6 8 30 40
Size and Weight 4 5 8 20 32
Technology Readiness
3 7 2 21 6
C Lif i 8 9 40 4Core Lifetime 5 8 9 40 45
Refuelling C l it
3 5 6 15 18Complexity
Plant Efficiency 4 4 7 16 28
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Totals: 142 169
Project InterfacesOUTPUTS
Safety & Security
INPUTS
Safety & Security Safety & Security•Fuel inventory
•HAZOP
Safety & Security•Limits on enrichment
•Reliability requirements for core materials
Shielding and Materials•Core Composition
•Fuel InventoryShielding and Materials
•Requirement for shielding •Core Power
Thermal Hydraulics
which may affect neutron population
CORE DESIGN
and Dynamics•Power, dimensions,
temperatures, poisons, delayed t f ti
Thermal Hydraulicsand Dynamics
•Temperature of coolant re-t i th neutron fractions
NavalisationC Si d W i ht
entering the core
NavalisationE li t
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•Core Size and Weight•Emergency cooling system•Shutdown requirements
Result BenchmarkingCore Arrangement
keffective -Homogeneous
keffective -Heterogeneous
Hyperion Power Generation g g
Coreg
Core EstimateAll Rods Inserted 0.8782 0.8561 0.871
All Rods Withdrawn
1.0918 1.0707 1.081
Control Rods 0.9534 0.9293 0.956Inserted OnlyEmergency Rods Inserted Only
0.9994 0.9734 0.954Inserted Only (Control Out)All Rods & Emergency Balls
0.8523 n/a n/aEmergency Balls Inserted
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Errors and Uncertainties• Minor inaccuracies in the geometry of the HT-9
volumes/ LBE downcomervolumes/ LBE downcomer
- Analysis of cross-sections performed
• Uncertainties in the Nuclear Data Library (NDL) referenced by MONK
• Random errors in the preparation and execution of the code
• Statistical uncertainty in the Monte Carlo method
• Standard MONK error keffective ± 0.0004
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Error Reduction• Simple
homogeneoushomogeneous model produced to test code volumetest code volume interpretation:- Volumes enteredVolumes entered
manually
- Failed to narrow the existing discrepancy
- Discounted as the source of the error
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2D Nodal Homogeneous Model Geometry
Error Reductiono educt o• WIMS10a Beta 4
provided by Sercoprovided by Serco- WIMSECCO
CACTUS3D- CACTUS3D• Homogeneous model
re-run using fine-group g g p(1968) energy spectrum
• New approach adopted• New approach adopted using ‘Sub-Meshing’- Increase in accuracy: y
k-value to within 3.06 % of stochastic results
A S b M h d C li d
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A Sub-Meshed Cylinder
Power Peaking Factors• The ratio of the flux in specific volumes of the core to the
average whole core flux
F ll dd d MIRIS HPMFully un-rodded core
MIRIS HPM
Maximum radial PPF 1.336 1.3
Maximum axial PPF 1.405 1.38
Maximum core PPF Results for Fully-Unrodded yHPM and MIRIS Cores
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Selection Matrix• Each reactor scored against weighted selection criteria
Selection Criterion
Weighting Factor
MIRIS Score
HPM Score
MIRIS Weighted
HPM WeightedCriterion Factor Score Score Weighted
ScoreWeighted
ScoreTemperature C ffi i t f
4 8 3 32 12Coefficient of
ReactivityAxial and Radial 2 4 5 8 10Power Peaking
(Burn-up Profile)Void Coefficient 4 7 4 28 16
of ReactivityThrough-Life
Reactivity/ Core4 8 3 32 12
Reactivity/ Core Lifespan
Power Density 2 6 7 12 14
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Totals: 114 64
Project InterfacesProject InterfacesSafety SafetySafety
•Safety FunctionRequirements
•End of Core Life &
Safety•Normal Operation &Accident Condition
Gamma Shine DosesAccident Inventories
Navalisation•Monitoring Equipment
•HAZOP
Navalisation•Operation / Accident Doses•Monitoring Equipment
•Manning•Refuel Process
•Operation / Accident DosesSHIELDING & MATERIALS
Thermal Hydraulicsand Dynamics
•Temperatures & Pressures
Thermal Hydraulicsand Dynamics
•Operating Zone
Reactor Physics & Core Design•Core Composition, Power
•Fuel Inventory
Reactor Physics & Core Design•Neutron Shielding
Requirements
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Accident DosesAccident DosesDose
MIRISDose (Sv/Hr)
Width: Hull 8.02E-05Width: Hull 8.02E 05
Length: Adjacent Compartment 1.60E-04
Height: Passenger Location 4.01E-05Height: Passenger Location 4.01E 05
Dose Hyperion (Sv/Hr)
Width: Hull 5.66E-05
Length: Adjacent Compartment 1.13E-04
Height: Passenger Location 2.83E-05
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Model Doses MIRISModel Doses - MIRISDose (µSv/hr)
LocationPrompt Gamma
Prompt Neutron
Delayed Gamma
Coolant Gamma Total
Above Reactor 3.21E-06 3.12E-04 3.28E-04 5.25E-04 1.17E-03
Aft Machinery Space 5.47E-06 4.26E-05 9.12E-05 5.37E-05 1.93E-04
RC Side 1.85E-06 4.98E-05 3.55E-05 9.27E-05 1.80E-04
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Model Doses HyperionModel Doses - HyperionDose (µSv/hr)
LocationPrompt Gamma
Prompt Neutron
Delayed Gamma Total
Above Reactor 2 76E-06 3 15E-04 3 84E-04 7 01E-04Above Reactor 2.76E 06 3.15E 04 3.84E 04 7.01E 04
Aft Machinery Space 6.18E-06 4.03E-05 8.05E-05 1.27E-04
RC Side 2.17E-06 5.08E-05 4.12E-05 9.42E-05
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Project InterfacesOUTPUTSINPUTS
Project InterfacesOUTPUTS
Core Design & Reactor Physics•Temperatures
INPUTS
Core Design & Reactor Physics•Core power & axial profiles
R d th •Transient responses•Rod worths•αT calculations
•Delayed neutron data
Navalisation•1o to 2o heat transfer •system requirements
Navalisation•Secondary systems
•Pump characteristics
THERMAL HYDRAULICS
AND DYNAMCIS
Safety & Security•Normal & accident transients
•HAZOP
Safety & Security•Safety functional requirements
HAZOP
Shielding & Materials•Temperatures & pressures
Shielding & Materials•Operating zone
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Methodology MIRISMethodology MIRIS
• Modelling – TRAC/PF1/MOD2:– 2 phase fluid code– Modifications for LOHS accident:
• Steam Generators• Auto SCRAM• Pressuriser delay valve• Safety relief valve• Safety relief valve• Containment with rupture valve
College of Management and Technology
Methodology TestingMethodology Testing
Reactor Model Test
Hand Normal Operation
MIRIS & Hyperion
Hand Calculations
Normal Operation
Natural Circulation
MATLAB /Normal OperationHyperion MATLAB /
Simulink Loss of Flow Accident
Loss of Heat Sink Accident
MIRIS TRAC L f H t Si k A id tMIRIS TRAC Loss of Heat Sink Accident
College of Management and Technology
Pillar SummaryPillar Summary
Selection Criterion
Weighting Factor
MIRIS Score
HPM Score
MIRIS Weighted
HPM WeightedCriterion Factor Score Score Weighted
ScoreWeighted
ScoreThermal Efficiency 4 4 6 16 24
4 7 5Plant Response 4 7 5 28 20Totals: 44 44
SMR Decision Matrix –Thermal Hydraulics & Reactor Dynamics
College of Management and Technology
Project InterfacesProject InterfacesINPUTS OUTPUTS
Navalisation and Economics
•Operating profile and
Navalisation andEconomics
SFR operating powersp g ppower requirements
•HAZOPShielding and Materials
•SFR, operating powers•Plant reliability figures
Shielding and Materials•SFR•Normal operation and
Accident Doses•HAZOP
•SFR•Inventory and accident
releaseThermal Hydraulics
SAFETY & SECURITY
Thermal Hydraulicsand Dynamics
•Accident modelingHAZOP
Thermal Hydraulicsand Dynamics
•Accident progression •SFR•HAZOP
Core Design•Fuel inventories,
• HAZOP
SFRCore Design
•SFR•Reliability figures
College of Management and Technology
• HAZOP y g•Limits on enrichment
Safety Case Methodology Flow ChartFlow Chart
Source: RRMP 32870
College of Management and Technology
Source: RRMP 32870
HAZID MethodsHAZID Methods
• CSF decomposition• Internal and external hazard reviewInternal and external hazard review• HAZOP 1• Fault Schedule production
College of Management and Technology
Example Fault ScheduleExample Fault Schedule Initiating
event causePreventative
measures PIE Protectivemeasuresevent cause measures measures
Continuous rod withdrawal Rod stop Loss of controlled
rod movementFast acting
SCRAM
esPostulated AccidentInitiating Cause
ses
quen
cePostulated Initiating
Event(PIE)
Accident
Cau
s
Con
seq(PIE)
C
PreventiveSafety
ProtectiveSafety
MitigatingSafety
College of Management and Technology
SafetyMeasures
SafetyMeasures
SafetyMeasures
Activity Results in Becquerel'sActivity Results in Becquerel sI t H i A ti it MIRIS A ti it (B )Isotope Hyperion Activity
(Bq)MIRIS Activity (Bq)
Kr - 85 2.37E+15 1.79E+15Kr 85 2.37E 15 1.79E 15Kr - 85m 7.80E+15 4.05E+15Sr - 90 1.77E+16 1.69E+16I - 131 9.19E+16 6.40E+16I - 133 4.97E+15 7.80E+16I - 135 3.68E+16 3.76E+16
Cs - 134 3.16E+10 6.84E+15Cs - 137 1.95E+16 1.91E+16Xe - 133 1.74E+17 1.44E+17B 140 1 56E+17 1 32E+17
College of Management and Technology
Ba - 140 1.56E+17 1.32E+17
Bow Tie DiagramBow Tie DiagramInitiating Cause
es
Postulated Initiating
Event
AccidentInitiating Cause
uses
quen
ceEvent(PIE)
Cau
Con
seq
C
PreventiveSafety
ProtectiveSafety
MitigatingSafetySafety
MeasuresSafety
MeasuresSafety
Measures
College of Management and Technology
Critical Safety Functions (CSF)Critical Safety Functions (CSF)
• Control of reactivity• Control of temperatureControl of temperature• Control of radiation exposure• Control of release of radioactive material
College of Management and Technology
Dose CalculationsDose Calculations
• Cloudshine dose• Inhalation doseInhalation dose• Skin contamination dose
College of Management and Technology
UK Regulatory SystemUK Regulatory System
• Office for Nuclear Regulation (ONR)• Nuclear Installations Act (NIA65)Nuclear Installations Act (NIA65)• Permissioning• 36 Licence Conditions• Not applicable to modes of transport• Not applicable to modes of transport
College of Management and Technology
Merchant Shipping RegulationMerchant Shipping Regulation
• International Maritime Organisation (IMO)• Safe Return to PortSafe Return to Port • Safety of Lives at Sea (SOLAS 7)
College of Management and Technology
ConsiderationsConsiderations
• Not covered by NIA65• Sovereign state nuclear policySovereign state nuclear policy• Security of nuclear material• Berth status• Ship classification• Ship classification• IMO• Nuclear safety
College of Management and Technology
Proposed Regulatory SystemProposed Regulatory SystemInternational
MaritimeOrganisation (IMO)
International AtomicEnergy Agency
International Association
of Classification Societies
InternationalNuclear
Inspectorate LloydsR i t
Sovereign StateNuclear Regulator
(in case of UK the ONR
Register
(in case of UK the ONR
Ship Builders
Licensee(Corporate Body)
IndependentNuclear ship
Safety Committee
College of Management and Technology
SecuritySecurity
• Comply with Licence Conditions• Comply with international legislationComply with international legislation• Provide consistency between flag states• Licensee’s responsibility
College of Management and Technology
IAEA Physical Protection yObjectives• Protect from theft• Recover missing/stolen materialRecover missing/stolen material• Protect against sabotage• Mitigate consequences of sabotage
College of Management and Technology
UK SystemUK System
• Office for Civil Nuclear Security (OCNS)• Produce security regulationsProduce security regulations• Site Security Plan (SSP)• OCNS inspections
College of Management and Technology
Safety and Security ScoringSafety and Security ScoringSelection C i i
Weighting F
MIRIS S
HPM S
MIRIS W i h d
HPM W i h dCriterion Factor Score Score Weighted
ScoreWeighted
ScorePassive 4 5 4 20 16Passive 4 5 4 20 16Active 4 5 6 20 24Inherent inDesign 4 4 6 16 24Containment 5 6 8 30 40Security andProliferation 3 7 5 21 15Inventory 3 6 6 18 18Inventory 3 6 6 18 18AccidentConsequence 5 7 5 35 25
College of Management and Technology
Totals: 160 162
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