セレーション翼を用いたウエルズタービンの空力騒音特性

抄録

In the present paper the attention is focused on the effect of trailing edge serrations on aerodynamic sound radiated from Wells Turbine for wave power conversion. We discussed the effect of trailing edge serrations on aerodynamic sound radiated from two-dimensional airfoil. At the two-dimensional airfoil with trailing edge serrations, discrete frequency noise clearly observed at small attack angle. The effects of trailing edge serrations, rotational speed and blade number on the aerodynamic sound radiated from Wells turbine were also investigated. The overall level of SPL increased as the rotational speed of Wells turbine increased. The noise proportional to the rotational speed and its overtone components increased. The SPL of normal Wells turbine gave in agreement with that of trailing edge serrations for lower frequency band. On the other hand, the SPL of serrations was larger than that of normal Wells turbine for higher frequency band. The discrete frequency noise was not observed for lower frequency band.