多孔质电极电火花加工极间流场仿真  

Simulation of Flow Field between Electrodes in Porous-electrode of Electrical Discharge Machining

作　　者：蒋毅 孔令蕾 金光远 平雪良 李其 

机构地区：[1]江南大学机械工程学院,江苏无锡214122 [2]江苏省食品先进制造装备技术重点实验室,江苏无锡214122

出　　处：《机床与液压》2016年第1期147-151,111,共6页Machine Tool & Hydraulics

基　　金：国家自然科学基金资助项目(51205169)

摘　　要：为研究多孔质电极电火花加工中分布式冲液对加工过程的作用机制,建立了多孔质电极极间流场模型,采用固液两相流数值方法模拟电极间冲液和蚀除产物的两相流动过程,与单孔电极进行了对比研究,并进行了电火花加工实验验证。仿真结果显示:多孔质电极的极间流场流速由于分布式冲液出口的存在而呈现分布式特征,且流场外围流速大于中心流速;采用多孔质电极后,由于分布式冲液出口的存在,能够将固相蚀除产物沿一定的通道有效排出加工区域。与仿真结果相对应,电火花加工实验结果表明:由于冲液对蚀除产物良好的排出作用,多孔质电极能够获得更高的加工效率,且加工速度随加工深度变化不大;但由于冲液影响了炭黑向工具电极的附着行为,导致工具电极相对损耗率增大。In order to investigate the mechanism of distributed flushing fluid in porous-electrode Electrical Discharge Machining( EDM),modeling of the gap flow field was carried out. The numercial method of solid-liquid two-phase flow was used to simulate the process of two-phase flow of flushing fluid in porous-electrode and solid debris,which was compared and investigated with that of single electrode to verify the EDM experimentally. The velocity of the flow between electrodes had a distributed feature because of the distributed outlet,and the periphery velocity was larger than that around center. After using porous-electrode,the solid debris was capable of evacuated the working area effectively along certain channels which resulting from the distributed flushing outlet. As compared with corresponding simulation results,the EDM experimental results show that the porous electrode is able to achieve a higher machining efficiency as a result of the evacuation effect of flushing fluid on debris,and the machining depth is affected by the machining speed weakly. On the other hand,as a result of the flushing influence on carbon adhesion to tool electrode,the tool wear rate is raised relaiely.

关 键 词：电火花加工 多孔质电极 流场仿真 固液两相流 

分 类 号：TG661[金属学及工艺—金属切削加工及机床]