Editorial: Thermal and Non-Thermal Plasmas at Atmospheric Pressure
Antonio D’Angola, Gianpiero Colonna, Е. В. Кустова
Abstract
One of the typical classifications of plasma systems identifies two major categories: thermal and nonthermal plasmas, in which the temperatures of the different plasma species are not the same. Thermal plasma technology has evolved over the past decades due to the increasing attention in fields such as aerospace, microelectronics, automotive, material treatment and processing, melting and welding of metals, plasma chemical synthesis, and vapor deposition, plasma and arc spraying, and waste destruction Typical atmospheric plasma devices are realized by means of arcs or radio frequency (RF) inductively coupled plasma discharges Modeling these phenomena requires the knowledge of thermodynamic properties and transport coefficients of plasmas Numerical codes reliably evaluating these data can assist the designing and optimizing the phases of plasma-based devices. Over the past decades, several numerical approaches have been developed to investigate plasma behaviors and commercial multi-purpose codes are often used due to the complexity of systems. These numerical codes are based on the fluid dynamics approach, describing realistic discharge geometries. The main drawbacks of thermal plasmas are represented by low excitation selectivity and very high gas temperatures; serious quenching requirements and electrode problems result in limited energy efficiency and applicability of thermal plasma sources. For these reasons, non-thermal plasmas such as low-pressure glow and RF, microwave discharges, dielectric barrier discharges, and laser-produced plasmas have been used due to their high selectivity in plasma chemical reactions, operating effectively at low temperatures and without quenching. More recently, non-thermal atmospheric pressure plasmas have been studied for a variety of industrial [9] and medical applications [10] such as sterilization, ozone production for water purification, pollution control applications, car exhaust emission control, volatile organic compounds removal, and polymer surface treatment in order to improve properties such as wettability, printability, and adhesion.