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INVESTIGATION OF AN INERTIAL CONFINEMENT FUSION-FISSION HYBRID REACTOR. Kiranjit Mejer PTNR Research Project 2009 Frazer-Nash Consultancy University of Birmingham. INVESTIGATION OF AN INERTIAL CONFINEMENT FUSION-FISSION HYBRID REACTOR. The Basic Concept Fusion neutron source - PowerPoint PPT Presentation
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SYSTEMS AND ENGINEERING TECHNOLOGY
INVESTIGATION OF AN INERTIAL CONFINEMENT FUSION-FISSION HYBRID REACTOR
INVESTIGATION OF AN INERTIAL CONFINEMENT FUSION-FISSION HYBRID
REACTOR
Kiranjit MejerPTNR Research Project 2009
Frazer-Nash ConsultancyUniversity of Birmingham
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
The Basic Concept
Fusion neutron sourceD + T → α + n + 17.6 MeV(n energy 14.1 MeV)
Sub critical fission blanket Neutron multiplier blanket Reflector
Benefits of a Hybrid
Waste transmutation – reducing inventory of HLW
Production of energy Development of fusion
technology Inherent safety
The Fusion-Fission Hybrid Reactor
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Laser Inertial confinement Fusion-Fission Energy Engine
Inertial confinement fusion source
Surrounded by Beryllium blanket Spherical blanket of sub-critical
fission fuel Graphite blanket Pb-Li first wall coolant FLiBe (2LiF+BeF2) coolant Power conversion system
Image from ”Thermal and Mechanical Design Aspects of the LIFE Engine” R P Abbot et al, 2009
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Multiplication Factor of Be Blanket
Pure 9Be – 1.85 gcm-3
Peak at 17 cm blanket thickness Factor ~ 2.06
Pebble packing fraction 60 % - 1.11 gcm-3
Factor ~ 1.81 at 16 cm Supported by “A Sustainable Nuclear
Fuel Cycle Based on Laser Inertial Fusion Energy” Moses et al, 2009
Neutron Multiplication Factor as a Function of Beryllium Blanket Thickness
0.5
0.7
0.9
1.1
1.3
1.5
1.7
1.9
2.1
2.3
0 5 10 15 20 25 30
Thickness/cm
Mul
tipl
icat
ion
Fac
tor
Neutron Multiplication Factor as a Function of Beryllium Blanket Thickness - 60 % packing
0.5
0.7
0.9
1.1
1.3
1.5
1.7
1.9
2.1
2.3
0 5 10 15 20 25 30 35 40
Thickness/cm
Mul
tipl
icat
ion
Fac
tor
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Fuel Blanket Investigation
Below - Energy gain from fission blanket of natural Uranium 19.1 gcm-3
surrounding a Beryllium blanket
Energy Gain vs Fuel Blanket Thickness - Natural U
0
5
10
15
20
25
0 10 20 30 40 50 60 70 80 90 100
Fuel Blanket thickness/cm
Ene
rgy
Gai
n
Energy Gain vs Fuel Blanket Thickness - U-238
0
0.5
1
1.5
2
2.5
3
0 10 20 30 40 50 60 70 80 90 100
Fuel Blanket thickness/cm
En
erg
y G
ain
Above - Energy gain from fission blanket of pure 238U
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Energy Spectrum of Neutrons
Neutron energy entering the fission blanket
~ 0.05 at 14 MeV Large proportion at thermal
energies
Maxwell-Boltzmann distribution peaks at 0.025 eV
Spectrum of neutrons returning from reflector shows same form
Thermal Neutron Energy Spectrum
0.00E+00
5.00E-03
1.00E-02
1.50E-02
2.00E-02
2.50E-02
3.00E-02
0.00E+00 5.00E-08 1.00E-07 1.50E-07 2.00E-07 2.50E-07 3.00E-07
Energy/MeV
Num
ber
(nor
mal
ised
per
sta
rtin
g n)
Fast Neutron Energy Spectrum
0.00
0.01
0.02
0.03
0.04
0.05
0.06
10.00 10.50 11.00 11.50 12.00 12.50 13.00 13.50 14.00 14.50
Energy/MeV
Num
ber
(nor
mal
ised
per
sou
rce
part
icle
)
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Other Fuel Options
radius 1 cm
Outer radius 0.5 mm Kernel radius 0.3 mm
Buffer layer (C)
High-density Pyc
SiC
coated particles embedded in graphite matrix
30% TRISO
70% Carbon Fuel composition based on graphite pebbles containing TRISO particles
Image adapted from http://blogs.princeton.edu/chm333/f2006/nuclear/trisoball.jpg
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Fission blanket energy gain and criticality
Fuel option Fission Energy Gain keff
Th-232 0.52 0.033
DU (0.26% 235U) 7.70 0.396
Natural U 16.08 0.576
LWR Spent Nuclear Fuel
27.60 0.720
Separated Transuranic Elements
183.14 0.966
Weapons grade plutonium
2.342
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Coolant Effects
First wall coolant Pb83Li17
Primary coolant FLiBe (2LiF + BeF2)
6Li + n → 4He + T + Q7Li + n → 4He + T + n’ – Q
Tritium Breeding Ratio (TBR) – ratio of T produced to consumed For self sufficiency TBR > 1.05 Requires 6Li enrichment of 50% or more
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Project Extensions
Improvements to the Model
Geometry – structural materials etc Fuel blanket compositions Temperatures Number of neutron histories Other fuel fabrication options Time dependent nature of the reactor - evolution of fuel with
breeding from fertile isotopes - flattening power output with 6Li content
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
Summary
Demand for clean, abundant energy and concerns over HLW management have led to renewed interest in the hybrid concept
MCNP modelling has demonstrated the viability of a number of fuel options particularly SNF
Enrichment of 6Li content in coolants can provide tritium self sufficiency for the reactor
Timescale for LIFE machine large
SYSTEMS AND ENGINEERING TECHNOLOGY
www.fnc.co.uk
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY
MCNP Model
Isotropic, monoenergetic neutron point source
Pb-Li first wall coolant Beryllium multiplier blanket Fission Blanket Graphite reflector
Stochastic approach - uses random number generation and reaction cross section data to determine the ‘history’ of a particle
Many histories followed to give a representation of a real world situation
© Frazer-Nash Consultancy Ltd 2010. All rights reserved. Confidential and proprietary document. SYSTEMS AND ENGINEERING TECHNOLOGY