Anatoliy T. Devices for microwave electromagnetic field forming for dielectric bulk materials exposure

The thesis is devoted to development of the methods of design of the devices for dielectric bulk materials irradiation with a microwave field which ensure uniform processing of the raw materials and high efficiency of the energy absorption. In order to calculate the energy transmission into the processing chamber the methods of investigation of reflection and transmission coefficients of arbitrary incident waves onto a polarization-selective surface and onto an interface between two dielectric media which separates the processing chamber from the external environment are developed. The efficiency improving methods of the devices are analyzed; in order to reduce the power reflection from the processing chamber the use of the matching dielectric wall combined with polarizing reflector is proposed. To reduce the power leakage from the processing chamber, its diameter should be calculated for sufficient waves attenuation to the critical power level. The analysis of the constituent elements of the working chamber such as polarization-selective reflectors and transpolarizing reflectors are performed, the analytical expressions for the scattered field are obtained as well as models for their numerical computer simulation. For the design of waveguide slot array for the processing chamber irradiation the backtracking algorithm is developed according to which the radiative elements are represented as equivalent circuit elements. The analysis of the field distribution near the array is carried out in order to establish the optimal distance from the emitter to the treated material. By means of simulation in HFSS the field distribution in the two described types of processing chambers filled with raw materials based on the opposite reflector and rotoreflector models when irradiated with eight and twelve irradiation array, respectively, is determined; herewith the rate of unevenness treatment of raw materials does not exceed 5%.