公路隧道中的粉尘颗粒物粒径范围分布较广,种类相对复杂,研究隧道中粉尘的去除有一定的现实意义。本研究采用静电除尘技术,通过模拟公路隧道不同情况下的各工况参数,考察了不同条件下静电除尘器的除尘效率。静电除尘器主体采用负直流高...公路隧道中的粉尘颗粒物粒径范围分布较广,种类相对复杂,研究隧道中粉尘的去除有一定的现实意义。本研究采用静电除尘技术,通过模拟公路隧道不同情况下的各工况参数,考察了不同条件下静电除尘器的除尘效率。静电除尘器主体采用负直流高压的电极供电形式,电极采用宽间距-长芒刺结构,实验粉尘选取烟尘、水泥粉和磷镁矿石粉模拟隧道粉尘。通过改变电源电压、风速、粉尘浓度、粉尘粒径和粉尘比电阻,分别计算了各条件下的除尘效率。实验结果表明,当电源电压为8.4 k V、风速4 m/s、粉尘浓度27.59 mg/m^3、粉尘颗粒物粒径60.71μm、粉尘比电阻适中的条件下,静电除尘器的除尘效率最高,可达90%。宽间距-长芒刺结构的静电除尘器对隧道中粉尘的去除有较理想的效果。展开更多
在大气压条件下,气隙距离为12 mm时,针—板DBD结构在不同的气体介质中会表现出不同的放电模式。当气体介质为氩气、放电电压为4 k V时,放电电压的正半周期表现为丝状放电模式,放电电压的负半周期为类辉光放电模式。当气体介质为氮气、...在大气压条件下,气隙距离为12 mm时,针—板DBD结构在不同的气体介质中会表现出不同的放电模式。当气体介质为氩气、放电电压为4 k V时,放电电压的正半周期表现为丝状放电模式,放电电压的负半周期为类辉光放电模式。当气体介质为氮气、放电电压为12 k V时,放电为电晕放电模式,但电压的正负半周期电晕放电模式也存在区别,在电压的负半周期,电流脉冲更加规则。当放电电压升高到15 k V,放电电压的正、负半周期会出现不同的放电模式,正半周期为丝状放电模式,负半周期呈现类辉光放电模式。在空气条件下,放电电压为12 k V时,存在和氮气条件下相似的电晕放电模式,而当放电电压为15 k V时,在整个周期只表现出丝状放电模式。展开更多
The classification of spatial characteristics and discharge modes of dielectric barrier discharge(DBD)are gaining increasing attention in industrial applications,especially in the field of surface treatment of materia...The classification of spatial characteristics and discharge modes of dielectric barrier discharge(DBD)are gaining increasing attention in industrial applications,especially in the field of surface treatment of materials.In this work,gray level histogram(GLH)and Fourier energy spectrum based on the digital image processing tech no logy are applied to investigate the spatial structure and discharge mode of mesh-plate DBD.The coefficient of variation(CV)is calculated to describe the uniformity of the discharge.The results show that the discharge mode of mesh-plate DBD changes from periodic discharge to filamentary discharge when the applied voltage increases from 11-15 kV.Moreover,a more regular spatial structure is obtained under lower applied voltages during the discharge process.It is also found that the apertures of mesh electrodes which are below 1 mm have smaller values of CV compared to plate electrodes,indicating more uniform discharge.Finally,polypropylene is treated by mesh-plate DBD for surface modification.The hydrophilicity is significantly improved as the water contact angle decreased by 64°,and the dyeing depth is also enhanced.展开更多
文摘公路隧道中的粉尘颗粒物粒径范围分布较广,种类相对复杂,研究隧道中粉尘的去除有一定的现实意义。本研究采用静电除尘技术,通过模拟公路隧道不同情况下的各工况参数,考察了不同条件下静电除尘器的除尘效率。静电除尘器主体采用负直流高压的电极供电形式,电极采用宽间距-长芒刺结构,实验粉尘选取烟尘、水泥粉和磷镁矿石粉模拟隧道粉尘。通过改变电源电压、风速、粉尘浓度、粉尘粒径和粉尘比电阻,分别计算了各条件下的除尘效率。实验结果表明,当电源电压为8.4 k V、风速4 m/s、粉尘浓度27.59 mg/m^3、粉尘颗粒物粒径60.71μm、粉尘比电阻适中的条件下,静电除尘器的除尘效率最高,可达90%。宽间距-长芒刺结构的静电除尘器对隧道中粉尘的去除有较理想的效果。
文摘在大气压条件下,气隙距离为12 mm时,针—板DBD结构在不同的气体介质中会表现出不同的放电模式。当气体介质为氩气、放电电压为4 k V时,放电电压的正半周期表现为丝状放电模式,放电电压的负半周期为类辉光放电模式。当气体介质为氮气、放电电压为12 k V时,放电为电晕放电模式,但电压的正负半周期电晕放电模式也存在区别,在电压的负半周期,电流脉冲更加规则。当放电电压升高到15 k V,放电电压的正、负半周期会出现不同的放电模式,正半周期为丝状放电模式,负半周期呈现类辉光放电模式。在空气条件下,放电电压为12 k V时,存在和氮气条件下相似的电晕放电模式,而当放电电压为15 k V时,在整个周期只表现出丝状放电模式。
基金financial support from the Joint Funds of National Natural Science Foundation of China(No.U1462105)
文摘The classification of spatial characteristics and discharge modes of dielectric barrier discharge(DBD)are gaining increasing attention in industrial applications,especially in the field of surface treatment of materials.In this work,gray level histogram(GLH)and Fourier energy spectrum based on the digital image processing tech no logy are applied to investigate the spatial structure and discharge mode of mesh-plate DBD.The coefficient of variation(CV)is calculated to describe the uniformity of the discharge.The results show that the discharge mode of mesh-plate DBD changes from periodic discharge to filamentary discharge when the applied voltage increases from 11-15 kV.Moreover,a more regular spatial structure is obtained under lower applied voltages during the discharge process.It is also found that the apertures of mesh electrodes which are below 1 mm have smaller values of CV compared to plate electrodes,indicating more uniform discharge.Finally,polypropylene is treated by mesh-plate DBD for surface modification.The hydrophilicity is significantly improved as the water contact angle decreased by 64°,and the dyeing depth is also enhanced.
