高速湍流下车顶绝缘子多相体放电机理及其防护措施研究

The roof insulation is a weak spot of the whole railway traction power supply system because of the limitation of space scale. In order to deal with the influence of extreme weather, such as rain, snow, fog, haze and sand, on the insulation of high speed electric locomotive roof, it is necessary to further study the insulation state of roof. This project is to take the multi-phase mixture particles in the near surface turbulence of the roof insulator as the research object. Analysis of the discharge law of multi-phase mixture in turbulence. Comparison of discharge phenomena in the air, to expound the effects of particles in multi-phase mixture and their related parameters on various discharge parameters; Using the modified dipole model as the prototype, to research the influence of the physical parameters in the multi-phase mixture and the distortion of the electric field on the surface of the particles, to conclude a universal mathematical and physical description of the local electric field in the dynamic distribution of multi-phase mixture particles; Study on the charge behavior of multi-phase mixture particles in turbulent discharge, to describe the influence of the parameters of the time-varying phase on the charge process of the multi-phase mixture particles; On the basis of the characteristics of multi-phase mixture discharge, to meet the target of roof insulation, using the multiplicative wave body design philosophy, following the Standard k-ε turbulence model, to give suggestions for roof insulation based on the characteristics of multi-phase mixture discharge in turbulence.

因空间尺度的限制，车顶绝缘一直是整个铁路牵引供电系统绝缘的薄弱环节。为了应对雨、雪、雾、霾、沙等极端气候对高速电力机车车顶绝缘的影响，有必要对车顶绝缘状态进行深入的研究。本课题拟以车顶绝缘子近表面湍流中的多相体颗粒作为研究对象，分析湍流中多相体的放电规律，对比普通空气中的放电现象，阐述多相体中颗粒及其相关参数对各个放电参数可能带来的影响；以修正偶极子模型为原型，研究多相体中相关物理参数与各颗粒表面的电场畸变的影响，归纳多相体动态分布下颗粒局部电场的普适性数学物理描述方法；探讨多相体颗粒在湍流放电中的荷电行为，描述时变物相参数对多相体介质颗粒荷电过程的影响；以多相体放电规律为基础，满足车顶绝缘的目标，利用乘波体的设计思想，遵循Standard k-ε湍流模型，提出基于湍流中多相体放电规律的车顶绝缘优化建议。

因空间尺度的限制，车顶绝缘一直是整个铁路牵引供电系统绝缘的薄弱环节。为了应对雨、雪、雾、霾、沙等极端气候对高速电力机车车顶绝缘的影响，有必要对车顶绝缘状态进行深入的研究。本课题以车顶绝缘子近表面湍流中的多相体颗粒作为研究对象，分析了湍流中多相体的放电规律，对比普通空气中的放电现象，阐述了多相体中颗粒及其相关参数对各个放电参数可能带来的影响；研究了多相体中相关物理参数与各颗粒表面的电场畸变的影响，归纳了多相体动态分布下颗粒局部电场的普适性数学物理描述方法；探讨了多相体颗粒在湍流放电中的荷电行为，描述了时变物相参数对多相体介质颗粒荷电过程的影响。