受电弓降弓过程弓网电弧等离子体动态特性研究

Dynamic Analysis of Pantograph-catenary Arc Plasma During Pantograph Lowering

以磁流体动力学(MHD)理论为基础,对Fluent流体软件进行二次开发,配合动态网格技术,建立弓网电弧仿真模型。仿真分析受电弓降弓过程中电弧温度场和气流场分布,同时计算分析在不同降弓速度下弧柱电压随间隙的变化规律,并且利用弓网电弧模拟试验平台测试降弓过程电弧电压随间隙的变化规律。研究结果表明,在受电弓降弓过程中,弧柱伸长,受电弓与接触网附近发生气流运动,弓网间隙间逐渐形成2个旋转方向相反的漩涡,电弧在气流的作用下发生热收缩效应。降弓速度越大,电弧电压随间隙的变化率越大。通过对比分析得知仿真结果符合试验结果的变化规律。

This paper focuses on the dynamic characteristics of pantograph-catenary arc plasma during pantograph lowering.Based on the theory of magnetohydrodynamics(MHD),secondary development was conducted for the Fluent fluid software.A pantograph-catenary arc model was established using the dynamic grid technique.Based on the simulation analysis of arc temperature field and airflow field distribution during pantograph lowering,the change law of arc column voltage with gap distance between the pantograph and catenary at different lowering speeds was calculated.The arc voltage during pantograph lowering was carried out by experimental pantograph-catenary system.The results show that the arc column is elongated during pantograph lowering.The airflow motion occurs and two vortexes which rotate in opposite directions generate between the pantograph and the catenary.The airflow motion results in the thermal pinch effect of arc plasma.The arc column voltage increases faster with higher pantograph lowering speed.The simulation results accord with experimental results.