軸流ファンの動翼後縁近傍の速度変動現象と空力騒音との関係

抄録

In the present paper the attention is focused on the relationship between velocity fluctuation in the near-wake of rotor blade and aerodynamic noise at the design operating condition of axial flow fan. We measured the relative velocity, turbulence intensity, spectrum of velocity fluctuation and time variation of velocity fluctuation near the trailing edge. The weak periodic Karman vortex was formed in the near-wake of the trailing edge of rotor blade. The prediction formula of SPL depended on the spanwise correlation length and turbulent intensity of weak vortex shedding. We discussed these parameters to predict SPL of aerodynamic noise generated from axial flow fan.