发动机叶片电解加工电解液流动方式优化及试验

Optimization and experimental investigation on electrolyte flow mode in ECM of turbine blades

提出新的主动控制的电解液流动方式,在该方式中,电解液从缘板两侧流入,分别流经叶盆、叶背流道.建立了流场数学模型,用有限元方法对流动方式进行分析,并与传统侧流式流动进行了对比,分析表明采用该主动控制型流动方式有助于流场的均匀稳定.为了验证该流动方式的合理性,进行了叶片电解加工对比试验.试验表明:与传统流动方式相比,采用新的主动控制流动方式,叶片的表面粗糙度从1.87提高到0.38,同时加工精度也提高了0.05mm,说明该流动方式设计合理,有利于提高叶片加工精度和表面质量.

The flow field in electrochemical machining （ECM） of turbine blade is studied. A mathematical model describing electrolyte flow in the interelectrode gap is developed and a new electrolyte flow mode named ＂active distributary mode＂ is proposed to machine turbine blade. In this mode, electrolyte flows from the platform of blade and is divided into two parts to flow across the convex and concave parts of blade individually. The flow mode is analyzed by finite element method and is compared with the traditional lateral flow modes. It is shown that the flow field in the interelectrode gap is more stable with the new flow mode. The experimental investigations were carried out in order to evaluate the rationality of the flow mode. The result reveals that the surface roughness can be improved to 0. 38 with the new flow mode. In contrast, the surface roughness of the blade profile with the traditional lateral flow mode is 1.87. The machining accuracy can also be enhanced 0. 05 mm. It can be concluded that the new flow mode is well designed and is in favour of improving the quality of turbine blade machined.