Fluid-dynamic effective rotor e.g. propeller, for use in e.g. ship, has contour regions arranged in relationship e.g. coincidental relationship, of part of rotor blades so that regions blow-out waves of specific wavelength and frequency

摘要

The rotor e.g. propeller (30), has rotor blades (31) arranged around a preset angle and spaced from each other about a rotational axis (34) and having a preset contour. The contour of the rotor blades has contour regions producing waves spreading in a fluid e.g. gas such as air, and liquid such as water, during rotation of the rotor about the rotational axis. The contour regions producing the waves are arranged in a relationship e.g. coincidental relationship, of a part of the rotor blades so that the contour regions blow-out waves of specific wavelength and frequency.