Development of 3-D Electromagnetic Thermal Fluid Simulation for Calculation of Metal Vapor Generated by ARC Discharge from Electrodes

Abstract

The objective of this simulation is to calculate the metal vapor which is generated by the arc from the electrode. The electricity is supplied to the electric railway while moving, because the contact wire and the contact strip are come into contact. At that time, the arc discharge occurs after the contact wire and the contact strip are separated because of poor contacting. The contact wire is damaged because fusion and evaporation is repeated by continuation of arc discharge. The generation of metal vapor is a factor of continuation of arc discharge. The metal vapor occurs when the temperature of the contact wire reaches the melting point. The electron density in arc increased with increasing the Cu vapor mixing rate in arc because ionization voltage of copper is lower than that of gas. Thus, the breakdown voltage decreases and the arc becomes easy to be maintained more. From the above, the contact wire disconnects in the worst case. It is necessary to figure out the damage mechanism for stable supply of electricity and long-life and low cost of facility. Some researchers have researched that the mass in molten area has been analyzed from damege of the contact wire at their experiment. However, the contact wire melted by arc discharge is changed in <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1 \mu \mathrm{s}$</tex> order. Therefore, the elucidation of physical phenomenon using numerical analysis is required. In this paper, the three dimensional electromagnetic thermal fluid simulation is developed to calculate metal vapor which is generated from electrodes heated by arc. As a result, the metal vapor was calculate from anode. The program under consideration of metal vapor conservation equation was created for calculation metal vapor. It is possible to calculation of metal vapor which the contact wire is heated by arc and melted.