Abstract: A finite element method pattern is built and the stress and deforming of contra-rotating axial fan impeller for mine local ventilator are analyzed. The reasons of blade fracture of larger type fans are the unreasonable structure and size of impeller, overpower stress of impeller root and over-low coefficient of safety as impellers rotate at high speed. The improvement measures are to increase the thickness of local impeller root and to improve the structure of impeller so as to reduce material consumption and enhance performance of the whole fan. Sample test and field using show that the mechanical strength and stiffness of after-improvement fan impeller meet the need. The weight of impeller is reduced by 20.8%; the noise is lowered by 2.31 dB and the effective value of vibration velocity is lessened by 1.5 mm/s, efficiency of total pressure is improved and range of stable running becomes wider. So it is probable to apply this analyzing method to like products.

Key words: Axial impeller, Deformation, Finite element method, Strength, Stress, Ventilator