The surface micro-discharge(SMD)excited by pulsed voltage in open air is experimentally studied by measuring its voltage,current,emission image,emission spectrum,and ultraviolet(UV)absorption spectrum.It is found that...The surface micro-discharge(SMD)excited by pulsed voltage in open air is experimentally studied by measuring its voltage,current,emission image,emission spectrum,and ultraviolet(UV)absorption spectrum.It is found that the SMD occurs intermittently in each cycle,and that it consists of many filaments on the surface of grounded electrode.While the applied voltage’s peak value Up increases from 1.75 kV to 7.25 kV,the discharge area keeps expanding until Up≈6 kV,when the discharge occupies all the available area.The emission spectrum of nitrogen metastable N2(C-B)and the density of ozone increase almost linearly.The ozone density decreases hyperbolically downstream of the grounded electrode due to the diffusion in open air.The characteristics of pulsed SMD are presented and analyzed as well,which may be referred by further investigations.展开更多
The results obtained from the research on the behaviour of fences (solid and porous) in the protection against particulated material emission to the atmosphere from open storage piles,are presented. This research was ...The results obtained from the research on the behaviour of fences (solid and porous) in the protection against particulated material emission to the atmosphere from open storage piles,are presented. This research was carried out through computational fluid dynamics (CFD) simulation by software Ansys CFX-10.0 in 3D,with K-epsilon being considered in the turbulence model. The efficiency of the use of porous fences as a protection against the wind flow,which interacts with an open storage pile,is shown. The use of these fences (when porosity is ε=30%) allows the reduction of wind flow velocity which interacts with the pile in comparison with the case of no use of fences (when porosity is 100%). In addition,the use of porous fences makes the velocity vortex,which is formed between the solid fence (ε=0%) and the pile,disappear,reducing the particle emission to the atmosphere by 78%.展开更多
基金Project supported by Fundamental Research Fund for the Central Universities of China,State Key Laboratory of Electrical Insulation and Power Equipment(EIPE11108)
文摘The surface micro-discharge(SMD)excited by pulsed voltage in open air is experimentally studied by measuring its voltage,current,emission image,emission spectrum,and ultraviolet(UV)absorption spectrum.It is found that the SMD occurs intermittently in each cycle,and that it consists of many filaments on the surface of grounded electrode.While the applied voltage’s peak value Up increases from 1.75 kV to 7.25 kV,the discharge area keeps expanding until Up≈6 kV,when the discharge occupies all the available area.The emission spectrum of nitrogen metastable N2(C-B)and the density of ozone increase almost linearly.The ozone density decreases hyperbolically downstream of the grounded electrode due to the diffusion in open air.The characteristics of pulsed SMD are presented and analyzed as well,which may be referred by further investigations.
基金the Spanish Ministry of Science and Education that granted these researches through the project CTM2005-00187/TECNO "Prediction Models and Prevention Systems in the Particle Atmospheric Pollution in an Industrial Environment" carried out at Oviedo University
文摘The results obtained from the research on the behaviour of fences (solid and porous) in the protection against particulated material emission to the atmosphere from open storage piles,are presented. This research was carried out through computational fluid dynamics (CFD) simulation by software Ansys CFX-10.0 in 3D,with K-epsilon being considered in the turbulence model. The efficiency of the use of porous fences as a protection against the wind flow,which interacts with an open storage pile,is shown. The use of these fences (when porosity is ε=30%) allows the reduction of wind flow velocity which interacts with the pile in comparison with the case of no use of fences (when porosity is 100%). In addition,the use of porous fences makes the velocity vortex,which is formed between the solid fence (ε=0%) and the pile,disappear,reducing the particle emission to the atmosphere by 78%.
