Ricerc@Sapienza

In the Water-Cooled Lithium Lead (WCLL) blanket, the eutectic alloy lithium-lead (PbLi) is used as tritium breeder and carrier, neutron multiplier, and heat transfer medium. The PbLi hydraulic loop section in the range of the reactor field coils, which includes the blanket and a non-negligible length of the connection pipes, is affected by intense magnetic fields which cause the transition to a MHD regime. Lorentz forces oppose the fluid motion and cause pressure losses several orders of magnitude higher than for the ordinary hydrodynamic regime.

A critical point in the design of liquid metal blankets for fusion reactors is the accurate estimate of magnetohydrodynamic (MHD) pressure losses caused by the interaction between flowing breeder and magnetic field. In the Water-Cooled Lithium Lead (WCLL), the liquid metal (PbLi) is used as tritium breeder and carrier, whereas power extraction is delegated to water, thus allowing to minimize the breeder velocity. However, pressure drop for the PbLi loop is expected to remain significant due to high field intensity and direct electrical contact at fluid/wall interface.