Numerical Investigation of an Unsteady Blade Surface Blowing Method to Reduce Rotor Blade-Vortex Interaction Noise

Figure 11

Near-body vortex structure from several azimuthal angles at the blade’s advancing side for the steady/unsteady blowing cases (isosurfaces of the criterion at , colored by vorticity magnitude).

(a) Nonblowing (baseline)

(b) Steady blowing

(c) Unsteady blowing