Thermal Analyse For Slow Wave System Of Millemeter Helix Traveling Wave Tube

The millimeter helix traveling wave tube has important application in electronic warfare, radar and satellite communications, remote sensing, and other fields, in which helix slow wave system is most important module. Thermal performance of the system is a key factor affecting the stability and reliability of traveling wave tube in normal working state. In this thesis, the thermal analyses for the system are investigated theoretically and experimentally so that it can provide a scientific basis for the improvement of the heat dissipation performance of the system.Firstly, the slow wave system including helix, rod and shell is studied by thermal analysis and modeling based on conductive heat transfer theory. Then thermal resistances between helix and rod as well as between rod and shell are also discussed, respectively. Secondly, the thermal analyzing model for dynamic electron beam in the tube is established by considering the actual situation of the electron gun area and the system according to the working state of the system. Also, the slow wave system analyzing model is established on the basis of the radiative heat transfer theory. Thirdly, by using ANSYS finite element software, the steady and transient thermal analysis of TWT is analyzed, and then the simulation results are analyzed, which are in good agreement with the theoretical analysis. Finally, based on the FBG temperature sensor and the thermocouple array of helix slow wave system interface thermal resistance test programs, a convenient helix interface thermal resistance test system is developed. This test system can measure the interface thermal resistance of slow wave system. After comparing among the experimental results, theoretical analysis, and the results of ANAYS simulation, it shows that built theoretical model and thermal resistance test results are consistent. Therefore, this theoretical model is able to provide reliable parameters for the establishment of a millimeter wave helix traveling wave tube slow wave system thermal analysis platform model.