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The previously developed governing equations for Magnetic Inertial Confinement Fusion, which combines the advantages of both magnetic and inertial confinement approaches, are improved to analyse a plasma beam in a linear device assisted by an external magnetic field. The equations are applied to simulate a steady state plasma beam sustained by a DC power supply as well as a transient beam generated by a separate pulsed discharge superimposed on the steady-state plasma. The calculated increase of plasma density during the pulse from the steady-state condition is compared with measurements using a laser interferometer at a relatively low voltage supply of 150 V for the pulses. The numerical and test results are found to agree within 20%. When the voltage rises, plasma instability is observed. This issue is inherent due to the use of a solid positive target electrode that blocks the plasma flow in the axial direction. As a remedy, additional tests were carried out using a hollow target electrode in a two-circuit design (to permit free gas flow in the axial direction) by replacing the DC power with transient, pulsed, highvoltage sources for plasma initiation and beam formation. These enhancements were successful in suppressing the instabilities. The peak plasma density was calculated at ∼10 22 m −3 for confinement times of the order of 1 ms. These results lie between the extremes for the current leading approaches yet are achieved for a more compact and inexpensive linear device.

A physical model has been developed which includes high temperature liquid lithium evaporation, the expanding motion of the liquid lithium vapour cloud, the shielding effects of the vapour cloud on incident plasma particle bombardments, ejection suppressed analysis and a perpendicular field proposal, and photon radiation, heat flux and transport in the lithium vapour cloud plasma. The engineering outline design scheme and the relevant parameters for the liquid lithium surface divertor target plate configured by discrete tiny capillary arrays have been established. Splashing can be suppressed by utilizing discrete and electrical insulating capillary porous systems (CPSs), since the conductivity among the capillary cells has been cut off by adopting a special kind of ceramic composite material made of a non-conducting and unbreakable composite which is able to withstand high temperatures. The formula to describe the temperature-dependent evaporation power has been derived. The maximum temperature increases of the discrete plasma-facing liquid lithium surface divertor target plate have been compared under the high energy flux deposition of 10 MJ m −2 during a 1 ms time duration with or without evaporation power. The results show that a high surface heat load can be withstood by the designed discrete plasma-facing liquid lithium surface divertor target plate due to violent evaporation. The energy deposition of incident energetic particles and weakly relativistic electrons from the scrape-off layer have been calculated. A laboratory experimental facility to simulate liquid lithium surface interactions with plasma has been set up. Research on lithium evaporation, re-deposition and ejection suppressed experiments under high density linear plasma dumping is ongoing.

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This article proposes a general framework for the conversion of U-238 and Th-232 utilizing fusion-produced neutrons. This recognizes that emerging fusion technologies may not produce sufficient net energy output to justify stand-alone applications, yet may be commercially viable for breeder transmutation or hybrid fusion-fission reactor concepts proposed herein to dispose of nuclear wastes and long life high radioactive fission products remaining in shutdown nuclear power plants. Results show that this could be achievable within a decade, given an appropriate fusion source. However, if 20% beryllium of nuclei density is added to the convertor blanket, the efficiency of the conversion process can be significantly increased. Also, the neutron energy spectrum resulting from dense D-D plasma core fusion is much softer than D-T fusion neutron source, hence the probability of (n, p) (n, α) backward decay reaction paths will be smaller and the conversion efficiency will be elevated.