Character of Flow Field on Turbine Blade with 3-Electrode Feeding Method in Electrochemical Machining

XU Zhengyang¹  ZHU Di¹  WANG Lei¹  SHI Xianchuan²

(1. College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016;
2. Department of Mechanical Engineering, Jiangsu Polytechnic University, Changzhou 213016)

Abstract: For making full use of the influence of flow field on blade electrochemical machining (ECM) and improving the accuracy and surface quality of blade, a mathematical model of electrolyte flow in the interelectrode gap is presented and the calculated distributions of several flow parameters such as volumetric gas-phase concentration, temperature, pressure and velocity of electrolyte are also given. A new electrolyte flow mode of “dual directional inlets” flow mode is developed for using the new 3-electrode feeding ECM tool of turbine blade. The clamping fixture for blade machining which applies the flow mode is also designed. The experimental investigations are carried out in order to evaluate the rationality of the designed flow field and the results reveal that the ac-curacy and surface quality of blade are enhanced.

Key words: Electrochemical machining (ECM)  Turbine blade  Flow field

CLC No: TG662

国家教育部博士点基金(20050287020)和航空科学基金(04H52055)资助项目. Received 20070430, received in revised form 20070927

References

[1] RAJURKAR K P, ZHU Di, MEGEOUGH J A, et al. New development in ECM[J]. Annals of CIRP, 1999, 48(2): 567-579.
[2] KOZAK J. Mathematical models for computer simulation of electrochemical machining processes[J]. Journal of Materials Processing Technology, 1998, 176: 170-175.
[3] RAJURKAR K P, WEI Bin, KOZAK J. Modeling and analysis of pulse ECM[J]. Annals of the CIRP, 1995, 44(1): 177-180.
[4] WILSON J F. Practice and theory of electrochemical machining[M]. New York, USA: Wiley-Interscience, 1971.
[5] ZHU Di. The latest advances and the principal issues in ECM[J]. Electromachining & Mould, 2000(1): 11-16.
[6] ZHU Di, WANG Kun, YANG Jianming. Design of elec-trode profile in electrochemical manufacturing process[J]. Annals of CIRP, 2003, 52(1): 169-172.
[7] LU Yonghua, ZHAO Dongbiao, YUN Naizhang, et al. Experimental research of on-line monitoring interelectrode gap of electrochemical machining based on 6d forces[J]. Chinese Journal of Mechanical Engineering, 2006, 42(7): 126-131.
[8] WANG Jianye, ZHANG Yongjun, YU Yanqing, et al. Recent advances of PECM(pulse ECM) in the precision/micro machining areas[J]. China Mechanical Engineering, 2007, 18(1): 114-119.
[9] SUN Chunhua, ZHU Di, LI Zhiyong, et al. Cathode de-sign and simulation of ECM turbine blade based on char-acteristics of liquid field[J]. Journal of Southeast Univer-sity (Natural Science Edition), 2004, 34(5): 613-617.
[10] CHANG C S, HOURGN L W, CHUNG C T. Tool design in electrochemical machining considering the effect of thermal-fluid properties[J]. Journal of Applied Electro-chemistry, 1999, 29: 321-330.
[11] LI Zhiyong, ZHU Di, SHI Xianchuan. Analysis of cathode feed direction and system design in electrochemical ma-chining of turbine blades[J]. Mechanical Science and Technology, 2004, 23(6): 712-715.
[12] SHI Xianchuan, ZHU Di, LI Zhiyong. Three-axis ECM system for machining blades[J]. Journal of South China University of Technology(Natural Science), 2004, 32(7): 70-73.