Thermal Analysis for Effective Cooling of a Millimeter-wave Mirror

Thermal analyses were carried out for a millimeter-wave mirror taking three different ways of surface heat load: i) over the full front reflecting surface of the mirror, ii) over the circular cross section (diameter 63.5mm) similar to that of RF beam over the front reflecting surface of the mirror, and iii) over the circular cross section (diameter 63.5mm) in Gaussian profiled manner on the front reflecting surface of the mirror. The thermal images were analyzed and the values of highest temperature attained and their location over the mirror were monitored. The highest temperature attained in three cases of heat load are 348.72, 330.53 and 391.64°C, respectively. Under practical consideration of Gaussian heat load, the maximum temperature attained was found below the allowable maximum temperature limit of 400°C and thus the proposed cooling found to be adequate for the case of heat load of 5kW.