电工技术学报2024，Vol.39Issue(23)：7616-7627,12.DOI:10.19595/j.cnki.1000-6753.tces.231860
进气流量对滑动电弧放电分解CO2的瞬态电-光-热特性和转化性能的影响
The Effect of Inlet Flow Rate on the Transient Electrical-Optical-Thermal Characteristics and Conversion Performance of CO2 Decomposition in Gliding Arc Discharges
摘要
Abstract
The rising concentration of carbon dioxide(CO2)is recognized as one of the most challenges in the 21st century.Non-equilibrium plasma can activate the reaction of CO2 decomposition at room temperature and pressure due to the abundant active particles.Gliding arc discharge(GAD),as a non-equilibrium plasma production method,has attracted the attention of researchers because of the high energy efficiency for CO2 decomposition.The inlet flow rate,as a key operational parameter,is directly related to the conversion performance of CO2 decomposition in GAD.However,current studies mainly focus on the CO2 conversion performance and lack the direct observation of the arc motion,optical,and thermal morphology.To address these issues,this paper aims to investigate the effect of inlet flow rate on the transient electrical-optical-thermal characteristics and conversion performance of CO2 decomposition in GAD by experiment. Firstly,an in-situ diagnostic platform for transient electrical-optical-thermal characteristics is built in this paper,in which the thermal characteristic is visualized by a high-speed Schlieren technology.Then,by using the diagnostic platform,this paper carries out the experiments of CO2 decomposition in gliding arc discharge under different inlet flow rates(1.5 L/min to 10 L/min).Typical gliding arc discharge results show that Schlieren images are an essential supplement to traditional mono-optical observation by revealing a high-temperature flow region composed of a high-temperature core and a high-temperature diffuse region. The effects of the inlet flow rate on the motion characteristic in GAD(i.e.,the discharge period and the arc short-circuit event),the area of the plasma luminescence and the high-temperature gas flow regions,the input energy,and the CO2 conversion performance parameters are compared and analyzed.The experimental results show that the discharge period decreases with the increase of the inlet flow rate,and the tendency follows an exponential decay distribution approximately.The areas of the plasma luminescence and high-temperature gas flow regions are positively correlated with the inlet flow rate,indicating that the increase in the inlet flow rate facilitates the expansion of the active particle and the enhancement of the heat convective to improve CO2 conversion.Two types of arc short-circuit events are induced by excessive inlet flow(10 L/min).The gliding region of GAD and the heat convection are suppressed due to frequent short-circuit events,resulting in the deterioration of CO2 conversion. The following conclusions can be drawn:(1)the discharge period decreases with the increase of the inlet flow rate,and the tendency follows an exponential decay distribution approximately.(2)There are two types of arc short-circuit events in gliding arc discharge:one is formed between the arc columns by electrical breakdown,and the other is formed in the near-cathode region by thermal breakdown.(3)The plasma luminescence area and high-temperature gas flow area increase with the inlet flow rate in a limited range,and reduce at excessive flow rates due to frequent arc short-circuit events.(4)The role of the inlet flow rate on CO2 conversion is mainly determined by the combined effect of gas residence time,active particle concentration and spatial distribution,heat convection,and short-circuit events.关键词
CO2分解/滑动电弧放电/进气流量/纹影技术/电-光-热特性Key words
CO2 decomposition/gliding arc discharge/inlet flow rate/Schlieren technology/electrical-optical-thermal characteristics分类
信息技术与安全科学引用本文复制引用
刘洋,章子潇,赵贤根,杜亚平,何俊佳..进气流量对滑动电弧放电分解CO2的瞬态电-光-热特性和转化性能的影响[J].电工技术学报,2024,39(23):7616-7627,12.基金项目
香港政府环境及自然保育基金资助项目(ECF26/2022). （ECF26/2022）
