SAR弧的磁层源区对应环电流与等离子体层顶重叠区域,而等离子体层顶常常观测到密度不规则结构.之前还没有暴时等离子体层顶密度不规则结构对SAR弧调制的观测报道.本文报道了地基成像和磁层、电离层卫星对2013年10月9日磁暴恢复相期间发...SAR弧的磁层源区对应环电流与等离子体层顶重叠区域,而等离子体层顶常常观测到密度不规则结构.之前还没有暴时等离子体层顶密度不规则结构对SAR弧调制的观测报道.本文报道了地基成像和磁层、电离层卫星对2013年10月9日磁暴恢复相期间发生的SAR弧的联合观测事件.在SAR弧的磁层源区,Van Allen Probe B卫星观测到了密度不规则结构,其中存在EMIC波、环电流离子分布和非线性电场结构.联合观测表明:该区域中的环电流离子分布通过库伦碰撞产生的热流通量足以驱动SAR弧,热流通量受到密度不规则结构的调制,形成空间上的小尺度分布,环电流离子中几keV的质子和几十keV的氧离子对这个过程起主导作用;此外,位于等离子体层顶密度不规则结构的低密度区的非线性结构电场引起的低能电子沉降可能是造成这次SAR弧非常明亮的原因.展开更多
The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification...The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification and discharge at the interface under certain condition. It is of significant importance to take an insight into the phenomenon occurring at the interface. Through experiment, the pressboard is found as a porous material. The interface changes abruptly from bulk pressboard to the bulk oil as a result of the porous structure. A new model is proposed which divides the interface into bulk oil region, transition region, and bulk pressboard region. The width of the transition region is decided according to the microtome figure. The effective permittivity of the transition region is calculated using a new model based on fractal theory. The model is validated and compared with previous calculation model. The effect of the existence of transition region on the electric field distribution is discussed.展开更多
文摘SAR弧的磁层源区对应环电流与等离子体层顶重叠区域,而等离子体层顶常常观测到密度不规则结构.之前还没有暴时等离子体层顶密度不规则结构对SAR弧调制的观测报道.本文报道了地基成像和磁层、电离层卫星对2013年10月9日磁暴恢复相期间发生的SAR弧的联合观测事件.在SAR弧的磁层源区,Van Allen Probe B卫星观测到了密度不规则结构,其中存在EMIC波、环电流离子分布和非线性电场结构.联合观测表明:该区域中的环电流离子分布通过库伦碰撞产生的热流通量足以驱动SAR弧,热流通量受到密度不规则结构的调制,形成空间上的小尺度分布,环电流离子中几keV的质子和几十keV的氧离子对这个过程起主导作用;此外,位于等离子体层顶密度不规则结构的低密度区的非线性结构电场引起的低能电子沉降可能是造成这次SAR弧非常明亮的原因.
基金Project(2009CB724504)supported by the National Basic Research Program of China
文摘The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification and discharge at the interface under certain condition. It is of significant importance to take an insight into the phenomenon occurring at the interface. Through experiment, the pressboard is found as a porous material. The interface changes abruptly from bulk pressboard to the bulk oil as a result of the porous structure. A new model is proposed which divides the interface into bulk oil region, transition region, and bulk pressboard region. The width of the transition region is decided according to the microtome figure. The effective permittivity of the transition region is calculated using a new model based on fractal theory. The model is validated and compared with previous calculation model. The effect of the existence of transition region on the electric field distribution is discussed.
