Modeling and Experimental Verification of Plasma Jet Electromagnetic Signals

Abstract

Herein, we discuss the modeling and verification of RF sensed signals in a simple plasma channel (plasma jet) at the generator frequency of f = 13.56 MHz, assuming plasma discharge at atmospheric pressure. The actual experiment was preceded by a basic numerical analysis and evaluation of several variants of the geometric/numerical model of a simple plasma channel formed in a glass capillary chamber; this step was performed with different electrode configurations. The analyses also included the impact of the location of the sensing element (i.e., the antenna) on the resulting evaluated electromagnetic signal. Furthermore, a numerical model with concentrated parameters facilitated a comparative analysis centered on the impact of plasma concentration and composition in the monitored electromagnetic RF spectrum of the channel. The theoretical outputs were verified via experiments and compared. This methodology finds use in the radio-frequency evaluation of plasma parameters in both simple capillary nozzles and more complex, slit-designed plasma chambers.

Modification of Insulating Properties of Surfaces of Dielectric High-Voltage Devices Using Plasma

“…The designing and testing of the PSJ were described in [35]. For the given purpose, a generator [36] with the output power of Pout = 10-1000 W, Uout = 300-600 V, a periodic signal, and a first harmonic of f1 = 13.56 MHz was used. The graphical patterns of the tests of changes in the surface resistance of the insulator as a function of time (from the exposure time without a precursor) are shown in Figures 9 and 10.…”

“…From previous research [36,37,44] on the properties of precursors of organic origin [36,42], the basic experiments with the effect of the plasma atmospheric discharge treatment [4][5][6][7] on the surface of the dielectric, together with the evaluation of changes in the relevant parameters, have moved to the application level (GA 20-14105S) [37,43]. In a recent article by Polášková et al [37], the scientifically proven mechanism of surface changes through the action of plasma generated by a slit jet is approached.…”

“…The result of the measurement of the incident plasma spectrum at the dielectric interface is exposed in Figure 11. The design and tests of the chamber have previously been published [9,10,12,36,44]. These chambers can be set up, and they parametrically affect the surface of the samples with plasma in a repeatable manner, monitoring and documenting the impact of plasma matter on the surface and the formation of artifacts (Figures 12 and 13).…”

“…process utilized a generator with the output power Pout = 10-1000 W, Uout = 300-600 V, a periodic signal, and the first harmonic f1 = 13.56 MHz (Figure 14). According to the previously performed experiments (from 1996 until now [4,7,9,10,35,36,45,46]), the parameters (Figure 11) of the electric power of the exciting slot nozzle of the plasma discharge in gases, for example, were obtained based on experiments with Ar, N2, etc., to effectively influence the surface. An example of the impact of changes in the plasma surface is shown in the images of the surface in Figure 12 under different settings of the discharge parameters.…”

“…Plasma discharge treatment at an atmospheric pressure nevertheless offers such an additional refinement of the insulator-dielectric surface. As shown above, these technologies are employed in other industrial domains; thus, the authors' research has centered on generating a suitable plasma discharge by a device usable in relevant branches of the industry [35,36].…”