Abstract :
A method of efficiently cooling tape-wound, edge-cooled magnet coils, or ferrite discs results from the action of an inwardly-directed spiral free vortex flow pattern of the coolant. Many of the unfavorable hydraulic losses and heat-transfer limitations inherent in conventional internally-cooled magnet coils can be eliminated or minimized. The designer can independently control fluid velocities, turbulence, heat-transfer rate, fluid flow rate, bulk temperature rise, and coil space factor within wide limits by the use of hydrodynamic techniques. Hydraulic pumping energy can be minimized, conductor temperature rise can be reduced, and in many cases, the electrical current density in the conductors can be raised by the use of external vortex coolant flow. The radial increase of fluid velocity toward the center matches the need for improved cooling of the inner portions of RF ferrite discs resulting from the increased heating at the inner rim. This reduces the hazard of thermal fracture in the brittle ferrite due to differential heating.
