High Power Gyrotron Output Window

Output window is the core of the gyrotron, which speciality can decide the speciality of the gyrotron greatly. The major subjects of output window design for high power gyrotron are to reduce the reflection and absorption power in order to enhance the gyrotron's stability and protect the output window. In this dissertation the output windows'refection and absorption are analyzed in detail.1.With the development of gyrotron, the output power of the gyrotron is higher and higher, but the destruction of output window is more and more outstanding. There are mainly two factors resulting the destruction of output window. One is that output window is cracked by the arcing on the surface of output window resulted by the secondary-electron ,the other is that the stresses result from intense local heating produced by the power dissipation due to the loss factor of dielectric of the output window cause the output window to rupture2.The second problem is now discussed in this dissertation. Combined with electromagnetic and heat transfer, FEM(finite element method) are used to analysis the temperature distribution in the output window result from pulse microwave and consecutive microwave of high power. The relation between temperature distribution and the loss factor of dielectric, the coefficient of heat transfer, output power, different modes, stress distribution are discussed.