{"title":"Experimental Study of the Discharge Characteristics of a Stepped-Nozzle Arc Plasma Torch","authors":"Kuan Li, Cheng Zhu, Yunfei Zhang, Zhaoyu Yu, Yuan Tian, Weidong Xia, Cheng Wang","doi":"10.1007/s11090-024-10481-9","DOIUrl":null,"url":null,"abstract":"<div><p>The stepped-nozzle arc plasma torch (SNAPT) is a promising arc source due to the advantages of high stability and high energy density, but the micro-time scale discharge characteristics have not yet been adequately investigated. In this study, a SNAPT was designed and studied, in order to investigate the effects of discharge current, gas flow rate, and nozzle morphology on the discharge characteristics. The results show that the volt-ampere characteristics of the SNAPT have an increasing curve when the gas flow rate is greater than 4 Nm<sup>3</sup>/h, and a decreasing curve when the gas flow rate is 3 Nm<sup>3</sup>/h. This result is related to the position of the arc root, and an arc constriction phenomenon occurs at high current and low gas flow rate. The thermal efficiency of the SNAPT decreases with the increasing current and decreasing gas flow rate, ranging from 69.6 to 82.3% within the experimental parameters. The optical emission spectroscopy results show that there are many active particles inside the plasma. The experimental parameters of the heavy particle temperature of 4851.5 to 9189.3 K and the electron temperature of 7846.9 to 10185.6 K both correspond to the Boltzmann distribution and are close to the local thermodynamic equilibrium state. Comparative experimental results show that the cylindrical-nozzle has the decreasing volt-ampere characteristics and higher voltages, but has large voltage fluctuations and poor stability compared with the stepped-nozzle. The results of the study are of guiding significance for design, selection of operating parameters, and application scenarios for this type of plasma torch.</p></div>","PeriodicalId":734,"journal":{"name":"Plasma Chemistry and Plasma Processing","volume":"44 4","pages":"1469 - 1492"},"PeriodicalIF":2.6000,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Chemistry and Plasma Processing","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11090-024-10481-9","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
The stepped-nozzle arc plasma torch (SNAPT) is a promising arc source due to the advantages of high stability and high energy density, but the micro-time scale discharge characteristics have not yet been adequately investigated. In this study, a SNAPT was designed and studied, in order to investigate the effects of discharge current, gas flow rate, and nozzle morphology on the discharge characteristics. The results show that the volt-ampere characteristics of the SNAPT have an increasing curve when the gas flow rate is greater than 4 Nm3/h, and a decreasing curve when the gas flow rate is 3 Nm3/h. This result is related to the position of the arc root, and an arc constriction phenomenon occurs at high current and low gas flow rate. The thermal efficiency of the SNAPT decreases with the increasing current and decreasing gas flow rate, ranging from 69.6 to 82.3% within the experimental parameters. The optical emission spectroscopy results show that there are many active particles inside the plasma. The experimental parameters of the heavy particle temperature of 4851.5 to 9189.3 K and the electron temperature of 7846.9 to 10185.6 K both correspond to the Boltzmann distribution and are close to the local thermodynamic equilibrium state. Comparative experimental results show that the cylindrical-nozzle has the decreasing volt-ampere characteristics and higher voltages, but has large voltage fluctuations and poor stability compared with the stepped-nozzle. The results of the study are of guiding significance for design, selection of operating parameters, and application scenarios for this type of plasma torch.
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.