考虑流场特性的发动机叶片电解加工阴极设计及数值仿真

Cathode design and simulation of ECM turbine blade based on characteristics of liquid field

为了提高阴极设计的精度 ,本文在考虑流场特性的基础上 ,分析了气泡率、温度、压力以及流速等因素对电解加工的影响 ,建立了电解加工间隙的数学模型 ,完成了叶片叶盆电解加工的阴极设计 ,同时对加工间隙中电场强度的分布进行了仿真 ,并和根据单纯考虑电场作用的模型所设计的阴极进行了对比 .结果表明 ,同时考虑流场和电场两因素时 ,间隙内的电场强度比单纯考虑电场因素时的电场强度大 9% ,其分布和叶片型面变化接近 ,说明考虑流场特性的阴极设计模型更能够真实的反映加工工件型面的变化 ,更加符合电解加工实际物理过程的本质 ,从而提高了阴极设计的精度 ,减少了阴极修正的次数 .

To increase precision of cathode design in electrochemical machining (ECM), a model for cathode design is built in view of characteristics of liquid field. Parameters affecting the distribution of gap, such as hydric bubble, temperature, pressure and liquid velocity, are taken into account. Cathode of turbine blade was designed according to the model. The electric field density was simulated and the results were compared with those from the cathode designed simply according to electric field. The results show that for newly designed cathode the distribution of electric field density is adapted to the surface of turbine. It implies that the model of cathode design based on characteristics of liquid field reflects the practical condition of the workpiece. Thus the precision of cathode design is increased and the number of reparation is reduced.