A microwave transparent method of cooling microwave components, with practical results

Microwave considerations often limit the means available for cooling waveguide-mounted components, to the detriment of performance. In fact, in high power microwave windows, thermal cracking is the usual average power limitation. The problem is further aggravated of the window is thin; heat conduction is along the long dimension of Figure 1a causing a maximum heat path length. It would be much better if heat could be made to flow laterally along the short path, and be removed directly from the faces of the heated areas. The paper describes a way to remove the heat as desired, using the heat pipe principle in a unique manner to provide a cooling path that has an effective conductivity much greater than that of solid copper, but is at the same time microwave transparent. The design of a working model of a heat pipe cooled microwave window is discussed.