A method for cooling RF waveguides on APT

The Accelerator Production of Tritium (APT) project will require up to 244 1-MW klystrons to provide radio frequency (RF) power for acceleration of a 100-mA proton beam. A major source of heat in the klystron gallery and the accelerator tunnel will be the RF waveguides, which conduct the RF power from the klystrons to the linac. Each waveguide is estimated to dissipate 11 kW of heat in the gallery and 17.5 kW in the tunnel. Base-case design called for conditioned-air cooling (to 104°F) of the tunnel space, with waveguide cooling by forced external convection. For more uniform and efficient waveguide cooling, several other techniques have been investigated, including water-cooling, cooling by nitrogen purging, and direct cooling of the waveguides by using them as air conditioning “ducts”. Models were created simulating the last technique. This paper reports on measurements to be made on the Low Energy Demonstration Accelerator (LEDA) at the Los Alamos National Laboratory (LANL) based on these models