Research Needs for Magnetic Fusion Energy Sciences - US Burning ...

The elements of a thrust to develop liquid metal PFcs are also important for liquid metal flows in
the blanket ducts contained in Thrust 13. They include:
1. magnetohydrodynamic modeling of liquid metal transport at high hartmann and
Reynolds numbers with fusion relevant fields, configuration and magnetic field gradients,
including the effect of plasma mhd on the stability of liquid metals. This activity is a
combination of theory, simulation and small laboratory experiments for validation.
2. a multi-laboratory effort to investigate substrate optimization (for slowly flowing
liquids), including capillary effects, as well as general chemical effects, temperature limits,
corrosion (including corrosion of neutron-irradiated materials), wetting, etc., is needed.
3. design and engineering of practical devices for injecting, controlling and removing liquid
metals in the presence of fusion-relevant magnetic fields.
4. design and engineering of systems to remove heat from liquid metal PFcs, for slowly
flowing liquid metals. Fast flowing liquids (e.g., jets) would carry the heat load with the
fluid.
5. a comprehensive liquid metal test stand capability. an adequate test stand should include
a liquid metal loop feeding and draining a target surface, with appropriate flow rates over
the surface, at a relevant magnetic field, and field angle to the surface. high heat flux
testing using e-beams or lasers should be available. The ability to perform simultaneous
Pmi studies, at least on a time scale appropriate to the residence time of the fluid on
the target surface, is desirable. comprehensive diagnostics of the liquid metal surface
behavior should be available.
6. Following test stand qualification, a plasma confinement device should test these liquid
metal systems with discharge durations in excess of the residence time of the fluid in the
system.
7. demonstration of high-power conversion efficiency using removed heat under demolike
conditions.
referenCes
J.C. Mankins, “Technology Readiness Levels, A White Paper,” Advanced Concepts Office, Office of
Space Access and Technology, NASA, April 6, 1995.
D.L. Youchison and M.T. North, “Thermal Performance of a Dual-Channel, Helium-Cooled, Tungsten
Heat Exchanger,” Fusion Technol. 39 2, 899-904 (2001).
E. Diegele, R. Kruessmann, S. Malang, P. Norajitra, G. Rizzi, “Modular He-cooled divertor for power
plant applications,” Fusion Eng. Des., 66-68, 383-387 (2003).
R. Majeski et al., Phys. Rev. Lett. 97 07, 5002 (2006).
A. Vertkov et al., Fusion Eng. Des., 82 15-24, 1627-1633 (2007).
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