Mgr. Ivan Soukup

This study presents the results of the numerical modeling of surface dielectric barrier discharge in planar configuration with the strips active electrode. A positive half-period of the sinusoidal driving voltage and the two-species case is assumed in this study. Currently, many numerical models of surface dielectric barrier discharge deal with different electrode geometries, longer timescales, or discharge energizations. However, the main innovation presented in this study is developing a three-dimensional numerical model for the initial phase of the discharge phenomenon and a deeper focus on the numerical theory behind it. Based on the fluid model, this study presents a detailed mathematical and numerical formulation of the problem, stable numerical reconstruction of ion and electron velocity fields and an explanation of the need for linear approximation of ionization rate. Finally, it computes the potential and electric field distributions, electron and ion densities, and their velocities. The obtained results of a numerical simulation showing trajectories and velocities of electrons and ions reflect the active region of the discharge. A numerical simulation demonstrates the method in a three-dimensional domain inspired by a real-life experiment. The model can be used to optimize the electrode geometry of the discharge.

This study examines the effect of airflow orientation with respect to the strip active electrode on concentration of ozone and nitrogen dioxide produced in a planar generator based on the surface dielectric barrier discharge. The orientation of the airflow was tested in parallel and perpendicular with respect to the strips. It was found that in the investigated range of average discharge power, the ozone concentration increases approximately by 25% when airflow was oriented in parallel with respect to the strips in comparison with perpendicular orientation of the airflow. Similarly the increase of nitrogen dioxide concentration was observed for parallel orientation of the airflow with respect to the strips in comparison with the perpendicular orientation of the airflow. Within the range of wavelengths from 250 to 1100 nm, the changes of intensities of spectral lines associated with airflow orientation have been observed. A 3D numerical model describing ion trajectories and airflow patterns have also been developed.