Investigating Energetic and Impedance Relations of Microwave Transmission Line Filled with Dielectric Material

Abstract

During microwave treatment, microwave energy is transferred to a material sample placed in an applicator of given geometric parameters. As a result of the energy transfer, the sample absorbs energy from the microwave field depending on its dielectric properties. The degree of energy absorption is directly proportional to the dielectric loss and proportional to the square root of the dielectric constant. The temperature of the sample continuously increases due to the energy transfer and the dielectric properties of the sample also change with the rising temperature. Although the microwave energy supply is constant, time and temperature dependent energy impedance and dielectric relations are developed. A part of them is measurable, but the other part of them can not be directly measured, they can only be computed from the previously measured ones. In a closed model which contains the parameters of the sample and the waveguide, the continuously changing parameters can be determined in relation of the temperature. These parameters are as follows: Attenuation of the transmission line, temporal change of the sample temperature, dielectric properties of the sample, loss factor of the sample, penetration depth, impedance of the transmission line, standing wave ratio reflection factor. The above parameters can be modeled as a function of the sample's temperature or as a function of time.

Dielectric Characteristics of Ionic Liquids and Usage in Advanced Energy Storage Cells

“…The modelling procedure was invented on the University of Pannonia by the research group. The above parameters can be modelled as a function of the sample's temperature or as a function of time [9].…”