Joseph D. Lee

Updated reference design of a liquid metal cooled tandem mirror fusion breeder

The current version of a reference design for a liquid-metal-cooled tandem mirror fusion breeder (fusion-fission hybrid reactor) is summarized. The design update incorporates the results of several recent studies that have attempted to resolve key technical issues that were associated with an earlier reference design completed in 1982. The issues addressed relate to the following areas of design and performance: nuclear performance, magnetohydrodynamic (MHD) pressure loading, beryllium multiplier lifetime, structural efficiency and lifetime, reactor safety, corrosion/mass transfer, and fusion breeder capital cost. The updated blanket design provides increased performance and reduced technological risk in comparison with earlier fission-suppressed hybrid blanket designs. Specifically, the blanket is expected to achieve a net fissile breeding ratio (per fusion) of 0.84, with a tritium breeding ratio of 1.06, and an average blanket energy multiplication of 2.44. It would operated at a relatively low neutron wall loading (1.7 MW/m/sup 2/) with a low lithium coolant outlet temperature (425/sup 0/C).

Fast-fission tokamak breeder reactors

A fast-fission blanket around a fusion plasma exploits high neutron multiplication for superior breeding and high-energy multiplication to generate significant net electrical power. A major improvement over previous fast-fission blanket concepts is the use of mobile fuel, namely a pebble-bed configuration with helium cooling. Upon loss of coolant, the mobile fuel can be gravity-dumped to a separately cooled dump tank before excessive temperatures are reached. The pebble bed is also compatible with rapid fuel exchange and a low-cost reprocessing method. With the ignited tokamak plasma producing 620 MW of fusion power, the net electric power is 1600 MWe and the annual fissile production exceeds 3 tonnes.

Neutronic investigation of inertial fusion energy blankets for HYLIFE-II and magnetohydrodynamic applications

The tritium breeding and energy absorption in an inertial fusion energy (IFE) reactor chamber have been investigated with variable coolant zone thickness using different materials. Examples are given for HYLIFE-II (an IFE reactor design) and for magnetohydrodynamic (MHD) energy conversion chambers using Flibe (Li[sub 2]BeF[sub 4]) as coolant. Investigations related to MHD are extended to the use of LiH, lithium, and Li17-Pb83 eutectic as working fluid. Natural lithium is used in all cases, except in the case of LiPb, for which both natural and enriched options were calculated. To achieve a useful energy density for energy conversion purposes with a sufficient tritium breeding ratio (TBR = 1.1 to 1.2), coolant zone thicknesses must be 25 cm for LiH, 50 to 60 cm for Flibe, and 80 cm for lithium. The use of Li17-Pb83 with natural lithium and with lithium enriched to 90% [sup 6]Li requires coolant zone thicknesses of 120 and 60 cm, respectively, to obtain a tritium breeding of TBR = 1.1, which gives an extremely low energy deposition density. This low density and the large coolant mass make LiPb unattractive for MHD and HYLIFE-II applications. 15 refs., 10 figs., 5 tabs.

Projections for a steady-state tokamak reactor based on the international thermonuclear experimental reactor

This paper examines the extensions of the physics and engineering guidelines for the International Thermonuclear Experimental Reactor (ITER) device needed for acceptable operating points for a steady-state tokamak power reactor. Noninductive current drive is provided in steady state by high-energy neutral beam injection in the plasma core, lower hybrid slow waves in the outer regions of the plasma, and bootstrap current. Three different levels of extension of the ITER physics/engineering guidelines, with differing assumptions on the possible plasma beta, elongation, and aspect ratio, are considered for power reactor applications. Plasma gain Q = fusion power/input power in excess of 20 and average neutron wall fluxes from 2.3 to 3.6 MW/m{sup 2} are predicted in devices with major radii varying from 7.0 to 6.0 m and aspect ratios from 2.9 to 4.3.

Surface conditions in a conceptual D--T mirror reactor with direct conversion

Abstract A conceptual D-T fusion reactor employing magnetic mirror confinement and periodic focusing electrostatic direct conversion is described with emphasis on surface conditions.

Economic analysis of a magnetic fusion production reactor

The magnetic fusion reactor for the production of nuclear weapon materials, based on a tandem mirror design, is estimated to have a capital cost of

Efficient Time-Independent Method for Conceptual Design Optimization of the National Ignition Facility Primary Shield

1.5 billion and to produce 10 kg of tritium/year for

Tritium breeding analysis of a tokamak magnetic fusion production reactor

22,000/g or 940 kg/year of plutonium in the plutonium mode for

Neutronic Data-Base Assessment for U.S. INTOR

250/g plus heavy metal processing. A tokamak-based design is estimated to cost

A non-inductively driven tokamak reactor based on ITER

1.5 billion and to produce 10 kg of tritium/year for