Numerical investigation on the comparison of the MHD flow features of lithium and eutectic lead-lithium alloy in a conduit with four-parallel ducts

Abstract

• The difference in the MHD (magnetohydrodynamics) flow characteristics between Lithium (Li) and eutectic lead-lithium (LiPb) is analyzed. • Commercial software CFX is used to investigate the LM MHD flows in a conduit with four-parallel ducts. • The effect of the local electric conductivity of the duct walls on the mass imbalance among the outlet ducts is investigated. • The mechanism governing the flow imbalance in the four-parallel ducts is discussed. • The pressure drop and mass flow rate in the case with Pb-17Li is larger than those in the case with pure Li. At present, the magnetohydrodynamic (MHD) flows of liquid-metal (LM) Pb-17Li and pure Li through a conduit with four-parallel ducts having partly different electrical conductivity are numerically analyzed. Here, the conduit system can cause counter flow and co-flow, which can be a good candidate for the design of duct flow in the liquid-metal blanket. Meanwhile, since lithium (Li) and eutectic lead-lithium (LiPb) are the promising liquid metal materials for a self-cooled blanket, the MHD flow characteristics of these two liquid metals become important and have to be taken into account during the design of a fusion liquid-metal blanket. The current study focuses on the electromagnetic features of the two liquid-metal flows, and considers the flow imbalance that is affected by different wall electrical conductivity in four-parallel ducts. The results present that the pressure drop and mass flow rate in the case with Pb-17Li is larger than those in the case with pure Li because of different properties of the liquid metals used therein. Furthermore, the influence of the local electrical conductivity of the structural walls on the flow imbalance among the outlet ducts is analyzed for the two different working fluids, and the mechanism governing the flow imbalance in the outlet ducts is discussed.