Liquid metal MHD and heat transfer in a tokamak blanket slotted coolant channel

A liquid metal MHD (magnetohydrodynamic)/heat transfer test was conducted at the ALEX (Argonne Liquid Metal Experiment) facility of ANL (Argonne National Laboratory), jointly between ANL and NIIEFA (Efremov Institute). The test section was a rectangular slotted channel geometry (meaning the channel has a high aspect ratio, in this case 10:1, and the long side is parallel to the applied magnetic field). Isothermal and heat transfer data were collected. A heat flux of ~9 W/cm² was applied to the top horizontal surface (the long side) of the test section. Hartmann numbers to 1050 (2 Tesla), interaction parameters to 9×10³, Peclet numbers of 10-200, based on the half-width of the small dimension (7 mm), and velocities of 1-75 cm/sec. were achieved. The working fluid was NaK (sodium potassium eutectic). All four interior walls were bare, 300-series stainless steel, conducting walls