Giacomo Pierotti, Arturo Popoli, Carlos Daniel Pintassilgo, Andrea Cristofolini
{"title":"Modeling Study of Chemical Kinetics and Vibrational Excitation in a Volumetric DBD in Humid Air at Atmospheric Pressure","authors":"Giacomo Pierotti, Arturo Popoli, Carlos Daniel Pintassilgo, Andrea Cristofolini","doi":"10.1007/s11090-024-10484-6","DOIUrl":null,"url":null,"abstract":"<div><p>A zero-dimensionl model is developed to study the chemical kinetics of a volumetric dielectric barrier discharge (DBD) reactor operating with humid air at atmospheric pressure. This work focuses on the relation between molecular vibrational excitation, the plasma reactor input power and the number densities of several species that are known to play an important role in biomedical applications (e.g. <span>\\(\\textrm{O}_{3},\\textrm{NO, NO}_{2}\\)</span>, ...). A preliminary study is carried out to observe the influence of water molecules on the electron energy distribution function for different values of water concentration and reduced electric field. A simplified approach is then adopted to quantify the contribution of vibrationally-excited <span>\\(\\textrm{O}_{2}\\)</span> molecules to <span>\\(\\textrm{NO}\\)</span> formation. The results obtained using our detailed model suggest that for the physical conditions considered in this work <span>\\(\\textrm{O}_{2}\\)</span> vibrational kinetics can be neglected without compromising the overall accuracy of the simulation. Finally, a reaction set is coupled with an equivalent circuit model to simulate the E-I characteristic of a typical DBD reactor. Different simulations were carried out considering different values of the average plasma input power densities. A particular focus was given to the influence of the Zeldovich mechanism on <span>\\(\\textrm{O}_{3}\\)</span> and <span>\\(\\textrm{NO}_\\textrm{X}\\)</span> production performing simulations where this reaction is not considered. The obtained results are shown and the role of vibrationally excited <span>\\(\\textrm{N}_{2}\\)</span> molecules is discussed. The simulation results indicate also that <span>\\(\\textrm{N}_{2}\\)</span> vibrational excitation, and more precisely the Zeldovich mechanism, has a larger effect on <span>\\(\\textrm{O}_{3}\\)</span> and <span>\\(\\textrm{NO}_\\textrm{X}\\)</span> production at intermediate input power levels.</p></div>","PeriodicalId":734,"journal":{"name":"Plasma Chemistry and Plasma Processing","volume":null,"pages":null},"PeriodicalIF":2.6000,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11090-024-10484-6.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Chemistry and Plasma Processing","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11090-024-10484-6","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract
A zero-dimensionl model is developed to study the chemical kinetics of a volumetric dielectric barrier discharge (DBD) reactor operating with humid air at atmospheric pressure. This work focuses on the relation between molecular vibrational excitation, the plasma reactor input power and the number densities of several species that are known to play an important role in biomedical applications (e.g. \(\textrm{O}_{3},\textrm{NO, NO}_{2}\), ...). A preliminary study is carried out to observe the influence of water molecules on the electron energy distribution function for different values of water concentration and reduced electric field. A simplified approach is then adopted to quantify the contribution of vibrationally-excited \(\textrm{O}_{2}\) molecules to \(\textrm{NO}\) formation. The results obtained using our detailed model suggest that for the physical conditions considered in this work \(\textrm{O}_{2}\) vibrational kinetics can be neglected without compromising the overall accuracy of the simulation. Finally, a reaction set is coupled with an equivalent circuit model to simulate the E-I characteristic of a typical DBD reactor. Different simulations were carried out considering different values of the average plasma input power densities. A particular focus was given to the influence of the Zeldovich mechanism on \(\textrm{O}_{3}\) and \(\textrm{NO}_\textrm{X}\) production performing simulations where this reaction is not considered. The obtained results are shown and the role of vibrationally excited \(\textrm{N}_{2}\) molecules is discussed. The simulation results indicate also that \(\textrm{N}_{2}\) vibrational excitation, and more precisely the Zeldovich mechanism, has a larger effect on \(\textrm{O}_{3}\) and \(\textrm{NO}_\textrm{X}\) production at intermediate input power levels.
期刊介绍:
Publishing original papers on fundamental and applied research in plasma chemistry and plasma processing, the scope of this journal includes processing plasmas ranging from non-thermal plasmas to thermal plasmas, and fundamental plasma studies as well as studies of specific plasma applications. Such applications include but are not limited to plasma catalysis, environmental processing including treatment of liquids and gases, biological applications of plasmas including plasma medicine and agriculture, surface modification and deposition, powder and nanostructure synthesis, energy applications including plasma combustion and reforming, resource recovery, coupling of plasmas and electrochemistry, and plasma etching. Studies of chemical kinetics in plasmas, and the interactions of plasmas with surfaces are also solicited. It is essential that submissions include substantial consideration of the role of the plasma, for example, the relevant plasma chemistry, plasma physics or plasma–surface interactions; manuscripts that consider solely the properties of materials or substances processed using a plasma are not within the journal’s scope.