Investigation on flow field in electrochemical trepanning of aero engine diffuser

Abstract

Electrochemical trepanning process is an economical approach of the electrochemical machining (ECM) for manufacturing ruled surface blade made of hard-to-cut material. In electrochemical trepanning, the flow field at the front gap is very important to influence the processing stability, efficiency, and surface quality. In this paper, the effect of cathode structure on flow field is investigated by simulation. An optimized cathode combining proper rounding at the internal orifice and insulation coating at external wall is obtained to improve the flow field uniformity at the front gap and enhance the electrolyte flow at the leading edge and trailing edge. Moreover, experiments were carried out, and results of the experiment show that the stability, efficiency, and surface quality of electrochemical trepanning are improved greatly by using the optimized cathode.