Polarizer miter bends for high-power microwave transmission: Ohmic loss and cooling

Waveguide miter bends with grooved mirrors are used to alter the polarization in oversized waveguides. The grooves increase the ohmic loss on the mirrors, and this increase is a function of the incident and output polarizations. In this paper, theoretical calculations of ohmic loss are compared with other available theory and experimental data. The optimum orientation and location of the polarizer miter bends for the lowest maximum ohmic loss is determined from the theory. Then the capability of polarizer miter bends to handle the heat loading at ITER is evaluated, using theoretical calculations of the ohmic loss and ANSYS modeling of the mirror cooling.