Study on flow field of electrochemical machining for large size blade

Abstract

Electrochemical machining (ECM) has become a mainstream manufacturing technology for parts with complex structures in aero-engines. In this work, the flow field of ECM of large size, super-twisted, and dual-platform blade is studied systematically, and some key difficulties are overcome. The cathodes optimal feeding direction of the blade is optimized by the maximum-minimization principle, and the results show that the optimal cathodes feeding angle α is 81°. A new flow field named tangential flow field is designed according to the blade's mean camber line, which effectively eliminates the defect of sudden change of flow channel in the traditional lateral flow field, and the non-uniformity of electrolyte flowing into the blade concave and blade convex is greatly improved due to the similar inflow angle. The flow field simulation results show that the flow velocity through the blade's concave surface and the blade's convex surface is similar, and the processing area also has a high flow velocity and is very orderly, and there is no turbulence. ECM experiments have verified that the machining process is very stable with the new flow field. The surface of the processed blades is very smooth without flow marks and short-circuit burns. In conclusion, the new tangential flow field has good machining stability and high surface quality, which can be used in engineering practice.