Coupled numerical simulation of arc plasma channel evolution and discharge crater formation in arc discharge machining

• Published in: International journal of heat and mass transfer Vol. 135; pp. 674 - 684
• Main Authors: Gu, Lin, Zhu, Yingmou, He, Guojian, Farhadi, Ahmad, Zhao, Wansheng
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.2019; Elsevier BV
• Subjects: Arc discharging; Computer simulation; Coupled model; Craters; Discharge; Discharge crater; Electric arcs; Electrodes; Empirical equations; Energy distribution; Erosion; Heat transfer; Machining; Mathematical models; Mathematical morphology; Plasma; Plasma arc heating; Simulation; Temperature distribution; Workpieces; Coupled model; Temperature distribution; Discharge crater; Heat transfer; Arc discharging
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2019.02.022

•A coupled electrode-plasma-workpiece model is proposed to study the plasma channel.•The equilibrium discharge numerical simulation is applied in the coupled model.•The electrical energy-thermal energy conversion and heat transfer is analyzed.•The temperature distribution of plasma channel, electrode and workpiece are obtained.•An observation experiment is conducted to verify the simulation results. A coupled electrode-plasma-workpiece mathematical model was proposed to study the development of arc plasma channels and the formation of discharge craters. In order to avoid deviations caused by heat source empirical equations and discrepancies in energy distribution type, a reliable simulation based on equilibrium discharge conditions was utilized to reveal the arc discharging process. To better describe this coupled model, the basic theoretical analysis of arc discharging was first introduced, after which the multi-field coupling and governing equations of arc discharging model were studied. Based on the simulation results, researchers investigated the heat transferred from the arc plasma channel to the workpiece and electrode and obtained the arc plasma shape. The discharge crater on the workpiece and the electrode erosion process were also analyzed. Additionally, a single arc discharging experiment was conducted in order to verify the simulation results. The experiment results reflect that the arc plasma shape and discharge crater morphology fits with the simulation results. The comparison indicates that the coupled electrode-plasma-workpiece model was effective in analyzing the arc discharging process.