高压放电破碎电介质材料仿真研究

Simulation study on dielectric materials broken by high voltage discharge

为了研究等离子通道的产生机制及电极结构对放电通道的影响,该文建立固-液混合介质三维模型,编制破岩仿真软件,设定电路参数及放电介质参数。通过改变电极形状、间距等,利用该软件对固-液混合介质等离子通道进行仿真,得到放电时通道及电极周围场的时空特性。仿真结果显示,脉冲发生器产生的脉冲由电极输入固体电介质后,固体电介质表面出现极化现象,产生等离子通道;等离子通道形成于不均匀固态电介质、液体电介质的交界处,放电通道能够在ms级的时间内聚集能量密度、迅速升温并产生巨大的压力;等离子通道周围的电场强度明显高于其他区域电场强度;等离子通道中的能量为总储能的20%~40%时可对固态电介质产生有效破碎。

In order to study the generation mechanism of a plasma channel and the effect of electrode structure on a discharge channel,a three-dimensional model of solid-liquid mixture medium is established ,and a rock-breaking simulation software is developed to set circuit parameters and discharge dielectric parameters. By changing the shape and spacing of the electrodes,the solid-liquid mixture plasma channel is simulated by the software,and the spatio-temporal characteristics of the channel and the field around the electrode are obtained. The simulation results show that polarization phenomenon occurs on the surface of the solid dielectrics and a plasma channel is generated after the pulse generated by the pulse generator inputs from the electrode to the solid dielectrics;the plasma channel formes at the junction of inhomogeneous solid dielectrics and liquid dielectrics,and the discharge channel can accumulate energy density in ms-level time and rapidly raise temperature to generate tremendous pressure;the electric field intensity around the plasma channel is obviously higher than that of other areas;the solid dielectrics can be effectively broken when the energy in the plasma channel is 20%~40% of the total energy storage.