Design of Unequally-Spaced Blade Arrangement for Tonal Noise Reduction

순음성 소음의 분산을 위한 부등간격 블레이드 설계 연구

  • Published : 2000.04.01


A numerical simulation was made to delineate the re-distribution of tonal noise generated from the equally-spaced blade passing frequency (BPF). A pressure-wave model was employed to analyze the tonal noise. An optimal solution for diversifying the tonal peak noise was obtained by rearranging the unequally-spaced blade angles. This was based on the fact that the noise energy is transferred from BPF to the neighboring frequency band. A limit condition for the minimum blade angle spacing was imposed. The unbalancing problem was also considered to avoid the weight bias.


Fan Noise;Unequally-Spaced Blade;Pressure Wave Mode


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