Numerical Investigation and Enhancement of Flushing Performance in the Micro-Electro Discharge Machining by Considering the Hole Depth and Dielectric Fluid

Authors

1 Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran

2 Department of Mechanical Engineering, K.N. Toosi University of Technology, Tehran, Iran

Abstract

flushing of machining gap is one of the most crucial issues in the micro-EDM that not only removes debris from the machining gap, but it also increases the machining efficiency. Identification of dielectric flow pattern provides a good perspective for its user to enhance the flushing performance. In this paper, the effects of the hole depth and dielectric fluid parameters on the flushing in micro-EDM are studied on the flushing in micro-EDM. Three different levels of 5, 10 and 15 mm for depth are considered, while deionized water, kerosene, and EDM-30 oil are chosen as dielectrics. To find out the effect of these parameters on flushing, computational fluid dynamics (CFD) based on boundary volume method is applied to solve the fluid flow in the flushing gap. To verify the numerical simulation model, a comparison was conducted between the results obtained in this work and the experimental and numerical results of the available literatures. The maximum difference between the results of this work and the experimental results is about 10.81%, which indicates that these results are in good agreement with the results of the previous research. The simulation was in a close agreement with them. By investigating the numerical results, it is observed that decreasing the depth of the hole and using deionized water as dielectric fluid increase the velocity of the flow in the flushing gap and reduce the size of the stagnation region in the hole.

Keywords


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